Magnetic sensing device for lid

Patent metadata

Field	Value
Publication number	US-10866290-B2
Application number	US-201916672741-A
Country	US
Kind code	B2
Filing date	Nov 4, 2019
Priority date	Jan 17, 2019
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

The technology provides for a magnetic sensing device. The device includes a magnetic sensor configured to generate a first output triggered by a first polarity and a second output triggered by a second polarity. The device includes a first magnet, a second magnet, and a third magnet. The device may be configured such that, when the second magnet is not within a predetermined distance from the first magnet, a magnetic field from the first magnet having the first polarity causes the first output and the second output to have a first set of values. The device may be configured such that, when the second magnet is within the predetermined distance from the first magnet, a magnetic field from the third magnet having the second polarity causes the first output and the second output to have a second set of values.

First claim

The invention claimed is:

1. A device, comprising:
a magnetic sensor, wherein a first output of the magnetic sensor is triggered by magnetic fields having a first polarity and a second output of the magnetic sensor is triggered by magnetic fields having a second polarity;
a first magnet, the first magnet being positioned at a fixed distance from the magnetic sensor;
a second magnet, the second magnet being positioned at an adjustable distance from the first magnet; and
a third magnet, the third magnet being positioned at an adjustable distance from the magnetic sensor;
wherein, when the second magnet is not within a predetermined distance from the first magnet, a magnetic field from the first magnet having the first polarity causes the first output and the second output to have a first set of values, and a magnetic field from a pole of the first magnet having the first polarity saturates the magnetic sensor; and
wherein, when the second magnet is within the predetermined distance from the first magnet, a magnetic field from the third magnet having the second polarity causes the first output and the second output to have a second set of values.

2. The device of claim 1 , wherein, when the second magnet is within the predetermined distance from the first magnet, a pole of the first magnet having the first polarity is configured to be facing a pole of the second magnet having the second polarity.

3. The device of claim 1 , wherein, when the second magnet is within the predetermined distance from the first magnet, a pole of the third magnet having the second polarity is configured to be facing a sensing surface of the magnetic sensor.

4. The device of claim 1 , wherein a strength of the first magnet or a distance between the first magnet and the magnetic sensor is selected such that, when the second magnet is not within the predetermined distance from the first magnet, a magnetic field from a pole of the first magnet having the first polarity saturates the magnetic sensor.

5. The device of claim 1 , wherein, when the second magnet is within the predetermined distance from the first magnet, a magnetic field from a pole of the third magnet having the second polarity saturates the magnetic sensor.

6. The device of claim 1 , wherein a strength of the third magnet is selected based on an operating point of the magnetic sensor or a distance between the second magnet and the third magnet is selected such that, when the second magnet is within the predetermined distance from the first magnet, a magnetic field from a pole of the third magnet having the second polarity saturates the magnetic sensor.

7. The device of claim 1 , wherein a strength of the first magnet and a strength of the second magnet are selected such that, when the second magnet is within the predetermined distance from the first magnet, a magnetic field from a pole of the first magnet and a magnetic field from a pole of the second magnet produce a magnetic attraction force between the first magnet and the second magnet meeting a threshold holding force.

8. The device of claim 1 , wherein the magnetic sensor is a dual output unipolar Hall Effect sensor.

9. The device of claim 1 , wherein the magnetic sensor includes a first unipolar Hall Effect sensor configured to be triggered by magnetic field of the first polarity, and a second unipolar Hall Effect sensor configured to be triggered by magnetic field of the second polarity.

10. The device of claim 1 , wherein the magnetic sensor and the first magnet are positioned within a body of a case, and the second magnet and the third magnet are positioned within a lid of the case; and wherein one or more processors of the case are configured to determine whether the case is open or closed based on at least one of the first output and the second output.

11. The device of claim 1 , wherein the magnetic sensor and the first magnet are positioned within a body of a case for housing one or more wireless devices, and the second magnet and the third magnet are positioned within the one or more wireless devices; and wherein one or more processors of the case are configured to determine whether the one or more wireless devices are positioned inside the case based on at least one of the first output and the second output.

12. The device of claim 1 , wherein the magnetic sensor and the first magnet are positioned within one or more wireless devices, and the second magnet and the third magnet are positioned within a case for housing the one or more wireless devices; and wherein one or more processors of the one or more wireless devices are configured to determine whether the one or more wireless devices are positioned inside the case based on at least one of the first output and the second output.

13. A device, comprising:
a magnetic sensor, wherein a first output of the magnetic sensor is triggered by magnetic field having a first polarity and a second output of the magnetic sensor is triggered by magnetic field having a second polarity;
a first magnet, the first magnet being positioned at a fixed distance from the magnetic sensor; and
a second magnet, the second magnet being positioned at an adjustable distance from the first magnet;
wherein, when the second magnet is not within a predetermined distance from the first magnet, a magnetic field from the first magnet having the first polarity causes the first output and the second output to have a first set of values; and
wherein, when the second magnet is within the predetermined distance from the first magnet, a magnetic field from the second magnet having the second polarity causes the first output and the second output to have a second set of values; and
wherein a strength of the second magnet is selected based on an operating point of the magnetic sensor such that, when the second magnet is within the predetermined distance from the first magnet, a magnetic field from a pole of the second magnet having the second polarity saturates the magnetic sensor.

14. The device of claim 13 , wherein, when the second magnet is within the predetermined distance from the first magnet, a pole of the first magnet having the first polarity is configured to be facing a pole of the second magnet having the second polarity.

15. The device of claim 13 , wherein, when the second magnet is within the predetermined distance from the first magnet, a pole of the second magnet having the second polarity is configured to be facing a sensing surface of the magnetic sensor.

16. The device of claim 13 , wherein the magnetic sensor and the first magnet are positioned within a body of a case, and the second magnet is positioned within a lid of the case; and wherein one or more processors of the case are configured to determine whether the case is open or closed based on at least one of the first output and the second output.

17. The device of claim 13 , wherein the magnetic sensor and the first magnet are positioned within a body of a case for housing one or more wireless devices, and the second magnet is positioned within the one or more wireless devices; and wherein one or more processors of the case are configured to determine whether the one or more wireless devices are positioned inside the case based on at least one of the first output and the second output.

18. A case, comprising:
a body;
a lid, the lid moveable with respect to the body between an opening and a closing position;
a magnetic sensor positioned at the body, wherein a first output of the magnetic sensor is triggered by magnetic field having a first polarity and a second output of th

Assignees

• Google Llc

Inventors

• Ding Yao
• Li Hui

Classifications

• G06F1/1677 Primary

  for detecting open or closed state or particular intermediate positions assumed by movable parts of the enclosure, e.g. detection of display lid position with respect to main body in a laptop, detection of opening of the cover of battery compartment · CPC title

• G01R33/072 Primary

  Constructional adaptation of the sensor to specific applications · CPC title

• H02J50/10

  using inductive coupling · CPC title

• H02J7/025

  Electricity · mapped topic