Rotation sensing device for detecting a fine displacement of a handle and control system in electrical power steering device
AssigneeSamsung Heavy Ind. Co., Ltd.
InventorChang-Soo Kim
Life of this patent
Estimating the term…
Abstract
A rotation sensing device for detecting a fine displacement of a handle and control system for use in an electrical power steering device in vehicles and a motor driving device in industrial machines. The rotation sensing device has a fixing member with a support plate and a plurality of polarity plates fixed to one side of the support plate at a predetermined interval, and a dielectric member with a plurality of dielectric plates fixed to one side of a handle shaft of the handle at a predetermined interval and movingly inserted into the interval between each of the polarity plates. Therefore, the capacitance of the dielectric member can be variable based on a mechanical displacement of the handle.
Claims2
A rotation sensing device for detecting a fine displacement of a handle shaft in an electrical power steering device comprising:
- a fixing member having a support plate and a plurality of polarity plates fixed to one side of said support plate, each of said polarity plates being spaced at a predetermined interval;
- and
- a dielectric member having a plurality of dielectric plates fixed to one side of said handle shaft, each of said dielectric plates being spaced at a predetermined interval and inserted into the interval between each of said polarity plates, whereby a capacitance of said dielectric member varies based on a mechanical displacement of said handle shaft, and wherein said handle shaft is inserted along cutout portions formed at one side of each of said polarity plates.
A control system in an electrical power steering device, comprising:
- a variable capacitance rotation sensor, having a fixing member consisting of a support plate and a plurality of polarity plates, and a dielectric member consisting of a plurality of dielectric plates for varying the capacity of said sensor in response to the displacement of a handle shaft of said electrical power steering device;
- an oscillator for generating an output voltage proportional to said variable capacitance of said rotation sensor;
- a reference voltage generator for generating a reference voltage comprised of triangular waveforms,
- an amplitude limiter connected to said oscillator for reducing noise from the output voltage of said oscillator;
- a filter connected to said amplitude limiter for passing only an output voltage from said oscillator within a predetermined frequency band;
- a voltage controlled oscillator connected to said filter and for generating a voltage proportional to an input signal from said filter;
- a differential circuit connected to said voltage controlled oscillator for differentiating the output voltage from said voltage controlled oscillator with respect to time;
- a comparator for comparing an output voltage of said differential circuit with said reference voltage and for generating a predetermined signal when said output voltage of said differential circuit is greater than said reference voltage;
- and
- a microprocessor for controlling a switching unit to determine the operation of a load in response to said signal from said comparator.
Dependencies are inferred from the claim text.