Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Phase difference detection device and method for a position detector










Image Number 11 for United States Patent #6885310.

Two A.C. output signals amplitude-modulated in accordance with two function values (sine and cosine) differing from each other in correspondence to a position-to-be-detected are received from a position sensor such as a resolver. By performing an addition or subtraction between a signal derived by shifting the electric phase of one of the received A.C. output signals by a predetermined angle, and the other received signal, two electric A.C. signals (sin(.omega.t.+-.d+.theta.), sin((.omega.t.+-.d-.theta.)) are electrically synthesized which have electric phase angles (.theta.) corresponding to the position-to-be-detected and are phase-shifted in opposite directions. ".+-.d" here represents phase variation error caused by factors, other than the position-to-be-detected, such as temperature change. In the synthesized two signals, the phase variation errors (.+-.d) appear in the same direction, while the phase differences (.theta.) corresponding to the position are shifted in opposite, positive and negative, directions. Thus, by measuring the respective phase shift amounts (.+-.d+.theta., .+-.d-.theta.) and performing appropriate operation, it is allowed to cancel out or extract the error (.+-.d) so that an accurate phase difference (.theta.) can be detected. Position detection data indicative of the detected phase difference (.theta.) is converted into a pulse-width-modulated signal and transmitted in the pulse-width-modulated form.








 
 
  Recently Added Patents
Pet urn enclosure
Cycloalkylamine substituted isoquinoline and isoquinolinone derivatives
Toilet
Searchlight
Control strategies for a multi-mode drive system
Apparatus and method for evaluating an activity distribution, and irradiation system
Apparatus for transmitting and receiving data in a wireless communication system and method thereof
  Randomly Featured Patents
Performance hydraulic systems for hybrid brake system
Valve structure having movable seat means
Pivotable connecting device
Image processor which manually and independently designates processing parameters for character data and image data
Radiation curable adhesive composition for surface protective film
Cyanate ester composites for oxygen containment
Snowboard
Hybrid vehicle control apparatus having a device for synchronizing friction members of one of two clutches corresponding to one of two different neutral states
Icon for a portion of a display screen
Frozen ice cream dessert and process for making