Oil pan with integrated capacitive sensor for measuring oil level

• US 9,587,534 B2
• Filed: 11/19/2015
• Issued: 03/07/2017
• Est. Priority Date: 02/11/2015
• Status: Active Grant

• Current Assignee: Flextronics America LLC (Flextronics International Limited)
• Original Assignee: Flextronics America LLC (Flextronics International Limited)
• Inventors: Holmes, Brian Wayne, Dhesikan, Rajagopalan, Stinson, Mei Ho, Huynh, Dung Dang, Correa, Jose Luis Tenorio, Bradford, Curtis Vance, Deva, Shaily, Hanna, John Nashed
• Primary Examiner(s): EL CHANTI, HUSSEIN A
• Application Number:
  US14/946,441
• Publication Number:
  US 20160230625A1
• Time in Patent Office: 474 Days
• Field of Search: 701/532
• US Class Current: 1/1
• CPC Class Codes: F01M 11/0004 Oilsumps
• CPC Class Codes: F01M 11/12 concerning lubricant level
• CPC Class Codes: G01F 23/265 for discrete levels
• CPC Class Codes: G01F 23/268 mounting arrangements of probes
• CPC Class Codes: G07C 5/02 Registering or indicating driving, working, idle, or waiting time only apparatus forming part of taximeters G07B13/00

Abstract

Embodiments provide an oil pan that includes an oil pan having a reservoir configured to hold oil and defined by one or more oil pan walls and an oil pan bottom. The oil pan includes one or more capacitance sensors coupled to a portion of the oil pan walls and configured to sense a capacitance. The oil pan includes a capacitance measuring unit electrically connected to the one or more sensors via one or more conductors and configured to receive each of the sensed capacitances via the one or more conductors and determine capacitance values for each of the sensed capacitances. The oil pan also includes a processor configured to receive the capacitance values and determine the oil level in the oil pan based on the capacitance values.

Claims

1. An oil pan comprising:

an oil pan bottom;

one or more oil pan walls extending a height between the oil pan bottom and a top of the oil pan walls;

a reservoir configured to hold oil, the reservoir defined by the one or more oil pan walls and the oil pan bottom;

three or more capacitance sensors, each capacitance sensor coupled to a portion of the one or more oil pan walls and each configured to sense a capacitance; and

a processor configured to determine an oil level in the oil pan based on sensed capacitances from each of the three or more capacitance sensors, wherein the processor is further configured to;

interpret the sensed capacitances from each of the three or more capacitance sensors as coordinates in space;

define a plane of a surface of the oil; and

determine the oil level based on the coordinates, the plane defined by the processor, and a center coordinate of the oil pan.

2. The oil pan of claim 1, further comprising:

a power source;

three or more conductors coupled to the three or more capacitance sensors; and

a capacitance measuring unit electrically connected to the three or more capacitance sensors via the three or more conductors and configured to receive each of the sensed capacitances via the three or more conductors and determine capacitance values for each of the sensed capacitances,

wherein the processor is configured to receive the capacitance values and determine the oil level in the oil pan based on the capacitance values.

3. The oil pan of claim 1, further comprising:

a transmitter configured to transmit an oil level value, corresponding to the oil level determined by the processor, to a computer to provide the oil level to a user.

4. The oil pan of claim 3, further comprising a receiver configured to receive a request from the computer to provide the oil level.

5. The oil pan of claim 4, wherein the transmitter and receiver are configured to communicate wirelessly.

6. The oil pan of claim 4, wherein the receiver is configured to receive a request for the oil level and the processor is configured to automatically provide the oil level upon receiving the request.

7. The oil pan of claim 1, wherein the processor is configured to automatically provide the oil level at equal time intervals.

8. The oil pan of claim 1, further comprising a storage unit, wherein the processor is further configured to store the oil level value in the storage unit.

9. The oil pan of claim 1, wherein the one or more oil pan walls are non-conductive and the three or more capacitance sensors are at least one of:

disposed inside the one or more oil pan walls and disposed outside of the oil pan walls.

10. The oil pan of claim 1, wherein the one or more oil pan walls are conductive and the three or more capacitance sensors are disposed on the inside of the one or more oil pan walls.

11. The oil pan of claim 2, further comprising a shield configured to house the three or more conductors, wherein the shield is configured to receive a signal from the capacitance measuring unit that cancels the capacitance of the three or more conductors and the capacitance measuring unit is configured to determine the capacitance values for each of the sensed capacitances without interference from capacitance of the three or more conductors.

12. The oil pan of claim 1, wherein,

the oil pan comprises two side walls, a front wall and a back wall,

the three or more capacitance sensors includes a first sensor located in a center line of the oil pan, a second sensor and a third sensor located on opposing side walls, and

the processor is further configured to determine the oil level based on:

the sensed capacitances from the first sensor, the second sensor and the third sensor;

a length of the oil pan from the front wall to the back wall; and

an equidistant length extending from the second sensor to the first sensor along the length of the oil pan and extending from the third sensor to the first sensor along the length of the oil pan.

13. An oil level measuring system for use with a motor vehicle, the oil level measuring system comprising:

an oil pan having a reservoir configured to hold oil;

three or more capacitance sensors, each capacitance sensor coupled to a portion of the oil pan and each configured to sense a capacitance at or proximate to the portion of the oil pan;

a power source;

three or more conductors coupled to the three or more capacitance sensors;

a capacitance measuring unit electrically connected to the three or more capacitance sensors via the three or more conductors and configured to receive each of the sensed capacitances via the three or more conductors and determine capacitance values for each of the sensed capacitances;

a processor configured to receive the capacitance values and determine an oil level in the oil pan based on the capacitance values, wherein the processor is further configured to;

interpret the sensed capacitances from each of the three or more capacitance sensors as coordinates in space;

define a plane of a surface of the oil; and

determine the oil level based on the coordinates, the plane defined by the processor, and a center coordinate of the oil pan.

14. The measuring system of claim 13, further comprising:

a motor vehicle computer configured to provide the oil level determined by the processor to a user; and

a transmitter configured to transmit an oil level value, corresponding to the oil level determined by the processor, to the motor vehicle computer.

15. The measuring system of claim 14, further comprising a receiver configured to receive a request from the motor vehicle computer to provide the oil level.

16. The measuring system of claim 15, wherein the transmitter and receiver are configured to communicate wirelessly.

17. The measuring system of claim 15, wherein the receiver is configured to receive a request from the motor vehicle computer in response to an occurrence of an event for the oil level and the processor is configured to automatically provide the oil level upon receiving the request from the motor vehicle computer in response to an occurrence event for the oil level.

18. The oil pan of claim 15, further comprising a user interface configured to receive the request to provide the oil level,

wherein the receiver is configured to receive the request and the processor is configured to automatically provide the oil level in response to the request.

20. The oil pan of claim 13, wherein,

the oil pan comprises two side walls, a front wall and a back wall,

the three or more capacitance sensors includes a first sensor located in a center line of the oil pan, a second sensor and a third sensor located on opposing side walls, and

the processor is further configured to determine the oil level based on:

the sensed capacitances from the first sensor, the second sensor and the third sensor;

a length of the oil pan from the front wall to the back wall; and

an equidistant length extending from the second sensor to the first sensor along the length of the oil pan and extending from the third sensor to the first sensor along the length of the oil pan.

19. A motor vehicle comprising:

a motor vehicle body; and

an oil level measuring system comprising;

an oil pan having a reservoir configured to hold oil;

three or more capacitance sensors, each capacitance sensor coupled to a portion of the oil pan and each configured to sense a capacitance at or proximate to the portion of the oil pan;

a power source;

three or more conductors coupled to the three or more capacitance sensors, wherein the three or more capacitance sensors includes a first sensor located in a center line of the oil pan, a second sensor and a third sensor located on opposing side walls;

a capacitance measuring unit electrically connected to the three or more capacitance sensors via the three or more conductors and configured to receive each of the sensed capacitances via the three or more conductors and determine capacitance values for each of the sensed capacitances;

a processor configured to receive the capacitance values and determine an oil level in the oil pan based on the capacitance values, wherein the processor is further configured to;

interpret the sensed capacitances from each of the three or more capacitance sensors as coordinates in space;

define a plane of a surface of the oil; and

determine the oil level based on the coordinates, the plane defined by the processor, and a center coordinate of the oil pan, wherein

the processor is further configured to determine the oil level based on;

the sensed capacitances from the first sensor, the second sensor and the third sensor;

a length of the oil pan from a front wall to a back wall; and

an equidistant length extending from the second sensor to the first sensor along the length of the oil pan and extending from the third sensor to the first sensor along the length of the oil pan; and

a motor vehicle computer configured to provide the oil level.