Gear sensing based on differential/asymmetric inductive sensing
AssigneeTexas Instruments Incorporated
InventorGeorge P. Reitsma
Life of this patent
Estimating the term…
Abstract
An inductive gear sensing system suitable for sensing gear (gear tooth) movement, such as some combination of speed, direction and position, based on differential sensor response waveforms. Example embodiments of inductive gear sensing with differential sensor response for different gear configurations include generating differential pulsed/phased sensor response signals from dual differential sensors based on axial (proximity-type) sensing for offset differential sensors (FIG. 1B, 102, 102; FIG. 2B, 201, 202), and generating asymmetrical response signals from a single sensor based on lateral and axial sensing with either asymmetrical gear teeth (FIG. 3A, 30A; FIG. 3B, 30B) or an asymmetrical sensor (FIG. 4B, 401) or a combination of both.
Claims15
An inductive sensing system suitable to sensing movement of a conductive gear, comprising:
- a conductive gear with gear teeth;
- and
- first and second inductive sensors disposed adjacent the gear, such that gear movement causes the gear teeth to move past the inductive sensors;
- each sensor operable to project a sensing area corresponding in size to the gear teeth, such that gear tooth movement past the sensor results in an axially-sensed sensor response pulse;
- the sensors arranged such that gear movement causes each gear tooth to move through the sensing area of the first sensor with a time differential relative to such gear tooth moving through the sensing area of the second sensor;
- such that the sensors are operable to provide respective differential sensor response pulses with a phase difference corresponding to the direction of movement of the gear teeth relative to the sensors.
A gear assembly, comprising:
- a conductive gear with gear teeth;
- and
- first and second inductive sensors disposed adjacent the gear, such that gear movement causes the gear teeth to move past the inductive sensors;
- each sensor operable to project a sensing area corresponding in size to the gear teeth, such that gear tooth movement past the sensor results in an axially-sensed sensor response pulse;
- the sensors arranged such that gear movement causes each gear tooth to move through the sensing area of the first sensor with a time differential relative to such gear tooth moving through the sensing area of the second sensor;
- such that the sensors are operable to provide respective differential sensor response pulses with a phase difference corresponding to the direction of movement of the gear teeth relative to the sensors.
A method of sensing gear movement suitable for use with a conductive gear with gear teeth, comprising:
- disposing first and second inductive sensors adjacent the gear, such that gear movement causes the gear teeth to move past the inductive sensors;
- configuring each sensor to project a sensing area corresponding in size to the gear teeth, such that gear tooth movement past the sensor results in an axially-sensed sensor response pulse;
- arranging the sensors such that gear movement causes each gear tooth to move through the sensing area of the first sensor with a time differential relative to such gear tooth moving through the sensing area of the second sensor;
- in response to gear movement, generating respective differential sensor response pulses with a phase difference corresponding to the direction of movement of the gear teeth relative to the sensors.
Dependencies are inferred from the claim text.