Operating an inductive energy transfer system

• US 10,193,372 B2
• Filed: 07/09/2015
• Issued: 01/29/2019
• Est. Priority Date: 09/02/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Herbst, Steven G., Morrison, Scott D., Alves, Jeffrey M., Garbus, Brandon R., Hwang, Jim C., Parnell, Robert S., Tikalsky, Terry L.
• Primary Examiner(s): Amrany, Adi
• Application Number:
  US14/795,723
• Publication Number:
  US 20160064992A1
• Time in Patent Office: 1,300 Days
• Field of Search: 307104
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices

Abstract

A receiver device in an inductive energy transfer system can include a touch sensing device. If the input surface of the touch sensing device is touched, a transmitter device can periodically stop transferring energy to allow the touch sensing device to sense touch samples while inductive energy transfer is inactive. Additionally or alternatively, a transmitter device can produce an averaged duty cycle by transferring energy to the receiver device for one or more periods at a first duty cycle step and for one or more periods at different second first duty cycle step. Additionally or alternatively, a transmitter device can reduce a current level received by a DC-to-AC converter if the current received by the DC-to-AC converter equals or exceeds a threshold. Additionally or alternatively, a transmitter device can ping a receiver device and transfer energy only after a response signal is received from the receiver device.

Claims

1. A method for operating an inductive energy transfer system that includes a transmitter device and a receiver device, the receiver device including a touch sensing device, the method comprising:

detecting if an input surface of the touch sensing device is touched while the transmitter device is transferring energy inductively to the receiver device; and

if the input surface is touched, the transmitter device transferring energy inductively only during a first time period and the touch sensing device obtaining touch samples only during a different second time period.

2. The method as in claim 1, further comprising determining if the input surface is being touched prior to the transmitter device transferring energy inductively to the receiver device.

3. The method as in claim 1, further comprising transferring energy inductively if a touch is not detected on the input surface of the touch sensing device.

4. The method as in claim 1, wherein the input surface of the touch sensing device comprises a cover glass disposed over a display.

5. The method as in claim 4, wherein the receiver device comprises a wearable communication device.

6. A method for operating an inductive energy transfer system that includes a transmitter device and a receiver device, the receiver device including a touch sensing device, the method comprising:

detecting if an input surface of the touch sensing device is touched while the transmitter device is transferring energy inductively to the receiver device;

if the input surface is touched, the receiver device transmitting a signal to the transmitter device;

the transmitter device turning off for a given period of time based on the signal received from the receiver device;

the touch sensing device obtaining touch samples while the transmitter device is turned off; and

after the given time period, the transmitter device turning on and transferring energy inductively to the receiver device.

7. The method as in claim 6, further comprising the receiver device suspending signal transmission to the transmitter device during the time period the transmitter device is turned off.

8. The method as in claim 6, wherein the input surface of the touch sensing device comprises a cover glass disposed over a display.

9. The method as in claim 8, wherein the receiver device comprises a wearable communication device.

10. A method for operating a capacitive sensing device with an inductive power receiver, the method comprising:

detecting an input to the capacitive sensing device; and

in response to detecting the input, receiving energy at the receiver device only during a first time period; and

further in response to detecting the input, operating the capacitive sensing device only during a second time period that is different from the first time period.

11. The method of claim 10, if the input is detected, the receiver device sending a signal to a transmitter device to transfer energy only during the first time period.

12. The method of claim 10, if the input is not detected, the receiver device receiving energy during both the first time period and the second time period.

13. The method of claim 10, wherein the capacitive sensing device comprises one of a touch sensor, an image sensor, or a biometric sensor.

14. The method of claim 10, further comprising determining whether the capacitive sensing device is mated with a transmitter device.

15. The method of claim 14, wherein the operation of determining that the capacitive sensing device is mated with the transmitter device occurs prior to determining if the capacitive sensing device detects the input.

16. The method of claim 10, wherein the input comprises a touch input.

17. The method of claim 10, wherein the input comprises a stylus input.

18. A method for operating a capacitive sensing receiver device with an inductive power transmitter, the method comprising:

detecting an input to the capacitive sensing device; and

in response to detecting the input, sending a signal to the inductive power transmitter to transfer energy only during a first time period; and

further in response to detecting the input, operating the capacitive sensing device only during a second time period that is different from the first time period.