SENSOR ASSEMBLY AND METHOD

• US 20090293584A1
• Filed: 06/02/2008
• Published: 12/03/2009
• Est. Priority Date: 06/02/2008
• Status: Active Grant

• Current Assignee: Custom Sensors & Technologies Incorporated (Schneider Electric SE)
• Original Assignee: Custom Sensors & Technologies Incorporated (Schneider Electric SE)
• Inventors: Casey, Gary, Nguyen, Nhan
• Granted Patent: US 8,082,807 B2
• Time in Patent Office: Days
• US Class Current: 73/1.63
• CPC Class Codes: G01D 11/245 Housings for sensors
• CPC Class Codes: G01D 3/036 on measuring arrangements themselves
• CPC Class Codes: G01L 15/00 Devices or apparatus for measuring two or more fluid pressure values simultaneously
• CPC Class Codes: G01L 9/125 with temperature compensating means non electric temperature compensating means G01L19/04

Abstract

Described herein is the sensor assembly and method for rapidly obtaining accurate readings of a variable. The sensor assembly comprises a plurality of sensors which are connected to a microcontroller that processes the signals of the individual transducers to the microcontroller. The microcontroller contains software that maximizes the refresh rate and/or minimizes the time it takes to process the outputs of each of the transducers. The microcontroller that is coupled to the sensor assembly selectively measures the outputs of each transducer so as to speed up the refresh rate of the sensor.

Claims

1. A sensor assembly for detecting a required variable, comprising:

a plurality of sensors with digital outputs, each detecting a reference output and an output responsive to a required variable, and

a microcontroller coupled to the output of each sensor, for controlling whether the reference output or the variable output of which sensor is detected and when.

2. The sensor assembly of claim 1, wherein the reference output is used to compensate for the environmental effects on the variable output in order to accurately determine the value of the variable.

3. The sensor assembly of claim 1 further comprising an interrupt for detecting the rising edge of each incoming pulse train representing the variable output of each sensor and for measuring the time it takes for a preselected number of incoming pulse trains to be detected and thereafter dividing that time by the preselected number to obtain an average pulse width for the variable output for each sensor, and after a predetermined number of averages has been obtained repeating the procedure to capture the average reference pulse width for each sensor, and thereafter repeating the process.

4. The sensor assembly of claim 1 further comprising a first layer having ports therein for exposing the sensors to the variable.

5. The sensor assembly of claim 1 further comprising a layer on which the plurality of sensors and the microcontroller is located.

6. The sensor assembly of claim 5 further comprising a top layer having ports therein for exposing the sensors to the variable and a bottom rigid layer with low thermal expansion on which the sensor layer is mounted.

7. A pressure sensor assembly, comprising:

a plurality of pressure sensors, each capable of detecting a reference pulse and a pulse responsive to pressure; and

a microcontroller for measuring the two pulses detected by each of the plurality of pressure sensors, such that the reference pulse of a particular sensor is used to compensate for the environmental effects on the pressure pulse detected by that same sensor to determine the pressure on a particular sensor;

wherein the microcontroller determines which pulses of which sensors are measured.

8. The pressure sensor assembly of claim 7, further comprising an interrupt for detecting the rising edge of each incoming pulse train representing the pressure output of each sensor and for measuring the time it takes for a preselected number of incoming pulse trains to be detected and thereafter dividing that time by the preselected number to obtain an average pulse width for the pressure output for each sensor, and after a predetermined number of averages has been obtained for the pressure output of a sensor repeating the procedure to capture the average reference pulse width for that sensor, and thereafter repeating the process.

9. A method for detecting the pressure in an automatic transmission having a plurality of clutches and an ECU, comprising the steps of:

coupling each of the clutches to a sensor located within a pressure assembly comprising a plurality of sensors;

detecting the pressure of each clutch as needed by detecting the pressure on the corresponding sensor a selected number of times and thereafter using the reference output detected by that sensor to compensate for the environmental effects on that sensor so that the true pressure may be obtained.

10. The method of claim 9, wherein the detecting step is performed by a microcontroller.

11. The method of claim 9, wherein the detecting step is performed by the ECU.

12. The method of claim 9, further comprising the steps of, calibrating the measurements of the pressures using calibration coefficients for each sensor, and thereafter determining if the reference output needs to be updated.