Magnetic holder for rechargeable devices

• US 20080150482A1
• Filed: 12/22/2006
• Published: 06/26/2008
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: VTech Telecommunications Limited (VTech Holdings Ltd.)
• Original Assignee: VTech Telecommunications Limited (VTech Holdings Ltd.)
• Inventors: Che, Kenny, Yazdi, Reza Ahmadian
• Granted Patent: US 7,801,573 B2
• Time in Patent Office: Days
• US Class Current: 320/115
• CPC Class Codes: H02J 7/0042 characterised by the mechanical construction

Abstract

A charger cradle used for charging a battery of a portable electrical device. An electromagnetic device is disposed within the charger cradle proximate a metal piece of the cordless handset when the cordless handset is placed in a receiving portion of the charger cradle. The electromagnetic device generates a magnetic field when charge contacts of the charger cradle and the cordless handset are in contact and a charging current is conducted from a charging circuit of the charger cradle. The magnetic field attracts the metal piece of the cordless handset and securely holds the cordless handset into the receiving portion while the charging circuit charges the battery of the cordless handset.

Claims

1. A charger cradle, comprising:

a receiving portion for receiving and holding a cordless handset therein, the receiving portion having an electrical contact for contacting with a charge contact of the cordless handset; and

a charging circuit for providing a charging current to the cordless handset through the contact of the electrical contact of the receiving portion and the charge contact of the cordless handset;

wherein the receiving portion includes a holding device that generates a magnetic field when the electrical contact of the receiving portion and the charge contact of the cordless handset contact with each other to attract the cordless handset securely into the receiving portion.

2. The charger cradle of claim 1, wherein the holding device includes a ferrite core and windings surrounding the ferrite core that generate the magnetic field when a charge current coming from the charging circuit flows there through.

3. The charger cradle of claim 1, wherein the cordless handset includes a metal piece proximate to the charge contact that is attracted by the holding device when the magnetic field is generated.

4. The charger cradle of claim 3, wherein the holding device includes a permanent magnet for attracting the cordless handset into the receiving portion.

5. The charge cradle of claim 4, wherein a permanent magnet holder is connected to the charging circuit by wires.

6. The charge cradle of claim 1, wherein a circuit for the holding device is separate from the charging circuit.

7. The charge cradle of claim 6, wherein a current flowing through the holding device is independent of the charging current provided by the charging circuit.

8. The charge cradle of claim 1, wherein a circuit for the holding device is serially connected with the charging circuit.

9. The charge cradle of claim 2, wherein the magnetic field is determined by one of charging current, number of windings, distance of the ferrite core and the coil windings, a length of the ferrite core, and a surface area of the ferrite core.

10. A charger cradle for charging a battery of a cordless handset, comprising:

a receiving portion for receiving the cordless handset, wherein the receiving portion includes an electrical contact, the electrical contact is located at a position corresponding to a charge contact of the cordless handset so that the electrical contact of the receiving portion contacts with the charge contact of the cordless handset;

a charging circuit for providing a charging current to charge the battery of the cordless handset when the electrical contact of the receiving portion is in contact with the charge contact of the cordless handset; and

an electromagnetic device proximate the receiving portion that generates a magnetic field when the electrical contact of the receiving portion and the charge contact of the cordless handset touch one another and the charging current is conducted through the electromagnetic device resulting in the magnetic field that attracts a metal piece of the cordless handset into the receiving portion.

11. The charge cradle of claim 10, wherein the metal piece of the cordless handset is located on a position corresponding to the electromagnetic device when the cordless handset is placed in the receiving portion.

12. The charge cradle of claim 10, wherein the electromagnetic device includes a ferrite core and windings surrounding the ferrite core that generate the magnetic field when a charge current coming from the charging circuit flows there through.

13. The charge cradle of claim 12, wherein the magnetic field is determined by at least one of the charging current, number of windings, distance of the ferrite core and the windings, a length of the ferrite core, and a surface area of the ferrite core.

14. The charge cradle of claim 10, wherein the electromagnetic device includes a permanent magnet for attracting the metal piece of the cordless handset into the receiving portion.

15. The charge cradle of claim 14, wherein a permanent magnet holder is connected to the charging circuit by wires.

16. The charge cradle of claim 10, wherein a circuit for the electromagnetic device is separate from the charging circuit.

17. The charge cradle of claim 16, wherein a current flowing through the electromagnetic device is independent of the charging current provided by the charging circuit.

18. The charge cradle of claim 10, wherein a circuit for the electromagnetic device is serially connected with the charging circuit.

20. The charge cradle of claim 18, wherein the permanent magnet is disposed in a magnet holder that is connected to the charging circuit by wires.

19. A charge cradle for charging a battery of a cordless handset, comprising:

a receiving portion for receiving the cordless handset, wherein the receiving portion includes an electrical contact, the electrical contact is located at a position corresponding to a charge contact of the cordless handset so that the electrical contact of the receiving portion contacts with the charge contact of the cordless handset;

a charging circuit for providing a charging current to charge the battery of the cordless handset when the electrical contact of the receiving portion is in contact with the charge contact of the cordless handset; and

a permanent magnet proximate to the receiving portion that generates a magnetic field that attracts the receiving portion and the charge contact of the cordless handset to one another.