Belt assembly allowing payout measurement

• US 10,272,872 B2
• Filed: 11/30/2016
• Issued: 04/30/2019
• Est. Priority Date: 11/30/2016
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Le, Jialiang, Rao, Manoharprasad K.
• Primary Examiner(s): Cass, Jean Paul
• Application Number:
  US15/365,160
• Publication Number:
  US 20180148014A1
• Time in Patent Office: 881 Days
• Field of Search: 701 46
• CPC Class Codes: B60R 2022/4825 for sensing amount of belt winded on retractor
• CPC Class Codes: B60R 2022/485 for sensing belt anchor position, belt orientation, or the like
• CPC Class Codes: B60R 21/01548 sensing the amount of belt winded on retractor
• CPC Class Codes: B60R 22/48 Control systems, alarms, or interlock systems, for the correct application of the belt or harness

Abstract

A belt assembly includes a belt, a first sensor and a second sensor. The belt has a webbing and a plurality of markers distinct from the webbing and fixed thereto. The markers are equally spaced a first longitudinal distance thereon in a longitudinal direction. The first sensor and the second sensor each have an associated detection field directed toward the belt and responsive to the markers in the fields. The second sensor is a second longitudinal distance from the first sensor differing from the first distance.

Claims

1. A belt assembly comprising:

a belt having a webbing and a plurality of markers distinct from and fixed thereto equally spaced a first longitudinal distance thereon in a longitudinal direction;

a first sensor and a second sensor each having an associated detection field directed toward the belt and responsive to the markers in the associated detection fields; and

the second sensor being a second longitudinal distance from the first sensor, the second longitudinal distance being less than the first longitudinal distance.

2. The belt assembly of claim 1, further comprising a belt retractor with the belt disposed retractably payable thereon.

3. The belt assembly of claim 2, comprising an anchor point spaced from the belt retractor and slideably receiving the webbing, the sensors being adjacent to the anchor point.

4. The belt assembly of claim 2, wherein the sensors are adjacent to the belt retractor.

5. The belt assembly of claim 1, wherein the markers are substantially rectangular in shape and substantially parallel to each other.

6. The belt assembly of claim 5, wherein the markers are elongated substantially perpendicular to the longitudinal direction of the webbing.

7. The belt assembly of claim 1, wherein the sensors are substantially identical.

8. The belt assembly of claim 1, wherein the sensors are proximity sensors.

9. The belt assembly of claim 1, wherein the second longitudinal distance is less than half the first longitudinal distance.

10. The belt assembly of claim 9, wherein the second longitudinal distance is substantially equal to one fourth the first longitudinal distance.

11. The belt assembly of claim 1, further comprising a computing device in communication with both sensors, the computing device programmed to determine:

occurrences of entry of at least one of the markers into the detection fields of the sensors, and

a direction of belt travel associated with the occurrences of entry.

12. The belt assembly of claim 11, further comprising a belt retractor with the belt disposed retractably payable thereon, and wherein the computing device is further programmed to determine a length of the webbing paid out of the belt retractor based on the direction of belt travel.

13. The belt assembly of claim 11, wherein the computing device is further programmed to:

establish a first time period equal to a time period between;

a first marker being sensed as entering into the detection field of the first sensor, and

an adjacent marker being sensed as entering into the detection field of the first sensor; and

establish a second time period equal to a time period between;

the first marker being sensed as entering into the detection field of the first sensor, and

one of the first marker and the adjacent marker being sensed as entering into the detection field of the second sensor, wherein the one of the first marker and the adjacent marker entering into the detection field of the second sensor occurs during the first time period.

14. The belt assembly of claim 13, wherein the computing device is further programmed to:

determine a ratio of the first time period to the second time period;

when the ratio is greater than two, identify the direction of belt travel past the sensors as being in a first direction; and

when the ratio is less than two, identify the direction of belt travel past the sensors as being in a second direction opposite the first direction of belt travel.

15. The belt assembly of claim 1, wherein the markers are formed of electrically conductive material.

16. A method of determining a belt payout, the method comprising the steps of:

providing a belt having a webbing and a first marker and a second marker, the first marker and the second marker distinct from and fixed to the webbing and equally spaced a first longitudinal distance in a longitudinal direction;

providing a belt retractor with the belt disposed retractably payable thereon;

providing a first sensor and a second sensor each having an associated detection field directed toward the belt and responsive to the markers in the fields, and the second sensor being a second longitudinal distance from the first sensor differing from the first longitudinal distance;

determining a first occurrence of entry of the first marker into the detection field of the first sensor;

determining a second occurrence of entry of the first marker in the detection field of the second sensor;

determining a direction of belt travel associated with the first occurrence of entry and the second occurrence of entry; and

determining a length of webbing paid out of the belt retractor based on at least on the direction of belt travel.

17. The method of claim 16, further comprising the steps of:

establishing a first time period equal to a time period between;

a first marker being sensed as entering into the detection field of the first sensor, and

an adjacent marker being sensed as entering into the detection field of the first sensor; and

establishing a second time period equal to a time period between;

the first marker being sensed as entering into the detection field of the first sensor, and

one of the first marker and the adjacent marker being sensed as entering into the detection field of the second sensor, wherein the one of the first marker and the adjacent marker entering into the detection field of the second sensor occurs during the first time period.

18. The method of claim 17, further comprising the steps of:

determining a ratio of the first time period to the second time period;

when the ratio is greater than two, identifying the direction of belt travel past the sensors as being in a first direction of belt travel; and

when the ratio is less than two, identifying the direction of belt travel past the sensors as being in a second direction of belt travel opposite the first direction of belt travel.

19. The method of claim 16, further comprising the step of placing the sensors adjacent to the belt retractor.

20. The method of claim 16, further comprising the step of using the length of webbing paid out to classify the seat occupant.