Texas Instruments Corporation

Lichang Cheng

Jun Zhang

Rujun Ji

Lei Zhang

Songhua Hu

Kangcheng Xu

Ziehen Qiu

Zichen Qiu

An apparatus is provided and includes a rotary encoder that comprises a stator, a rotor, and a controller. The stator has an opening adapted to surround a first portion of a rotatable shaft, a transmit region, and a receive region. The rotor has an opening adapted to surround a second portion of the rotatable shaft, an annular conductive region, and at least one conductor electrically coupled with the annular conductive region. The controller has an input coupled to the receive region and has an output coupled to the transmit region. The controller is configured to transmit a first signal on the output of the controller and to the transmit region of the stator, receive a second signal on the input of the controller and from the receive region of the stator, and determine, based on the second signal, a proximity of the at least one conductor to the receive region.

Capacitive-sensing rotary encoder

Methods and apparatus to determine a position of a rotatable shaft of a motor are disclosed. An example apparatus to determine a position of a rotatable shaft of a motor includes a sensor printed circuit board (PCB) structured to be mounted to a motor, the sensor PCB including a plurality of capacitive sensors, the plurality of capacitive sensors having respective ones of a plurality of capacitances that independently change as a conductor moves relative to the sensor PCB in conjunction with a rotatable shaft of the motor during an operation of the motor, and a controller electrically coupled to the sensor PCB, the controller configured to determine a position of the rotatable shaft based on the plurality of capacitances.

Methods and apparatus to determine a position of a rotatable shaft of a motor

Example capacitive-sensing rotary encoders and methods are disclosed herein. An example apparatus includes a rotary encoder structured to be mounted to a motor, the rotary encoder including a plurality of circumferential capacitive sensor arrays, each of the plurality of capacitive sensor arrays having an output representing a binary bit of a rotary encoder output, the rotary encoder output changing as a conductor rotates responsive to a rotatable shaft of the motor relative to the rotary encoder.

Capacitive-sensing rotary encoders and methods

Growing community of inventors

Shanghai, China

Lichang Cheng