Circuit arrangement and method for inductive energy transfer

• US 8,471,547 B2
• Filed: 12/09/2011
• Issued: 06/25/2013
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Braun GmbH (The Procter & Gamble Company)
• Original Assignee: Braun GmbH (The Procter & Gamble Company)
• Inventors: Jung, Philipp, Lepper, Joachim, Langsdorf, Jan Christian, Hohmann, Thomas, Petzold, Herbert, Herzberg, Lutz Ronald
• Primary Examiner(s): BERHANE, ADOLF D
• Application Number:
  US13/315,320
• Publication Number:
  US 20120105044A1
• Time in Patent Office: 564 Days
• Field of Search: 323/304, 323/305, 323/355, 323/356, 307/104, 307/108
• US Class Current: 323/305
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 7/05 Capacitor coupled rectifiers
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A circuit arrangement for the inductive transfer of energy is disclosed. The circuit arrangement includes an oscillator; a power supply for supplying the oscillator with energy and having a complex input resistance; and a device for detecting the inductive load of the oscillator and for modifying the complex input resistance of the power supply depending on the load of the oscillator.

Claims

1. A circuit arrangement for the inductive transfer of energy comprising:

an oscillator;

a power supply for supplying the oscillator with energy and having a complex input resistance; and

a device for detecting the inductive load of the oscillator and for modifying the complex input resistance of the power supply depending on the load of the oscillator;

wherein the power supply has a capacitive series resistance, a rectifier and a load resistance; and

wherein the capacitive series resistance may be modified depending on the load of the oscillator, such that the non-reactive power consumption of the circuit arrangement is reduced when the load of the oscillator is lower.

2. The circuit arrangement according to claim 1, wherein the load resistance may be modified depending on the load of the oscillator, such that the non-reactive power consumption of the circuit arrangement is reduced when the load of the oscillator is lower.

3. The circuit arrangement according to claim 2, wherein the load resistance is formed by at least one resistor and the switching path of a controllable switch, such that an ohmic resistance of the arrangement formed by the at least one resistor and the switch is switchable.

4. The circuit arrangement according to claim 2, wherein the load resistance is formed by the oscillator.

5. The circuit according to claim 4, wherein the oscillator is a Hartley or Colpitts oscillator with an active element.

6. The circuit arrangement according to claim 1, wherein the capacitive series resistance is formed by at least one capacitor and by the switching path of at least one controllable switch, such that the non-reactive resistance of the arrangement formed by the capacitor and the switch is switchable.