US 5,877,955 A · Transducerless position determining system and method for the same

Abstract

A transducerless position determining system and method of using the same for determining the relative position of a mechanical member or component which is driven by an electric motor within an electromechanical system. The transducerless position determining system includes a microcontroller with a software model that simulates the acceleration, deceleration and velocity characteristics of the electric motor as a function of applied voltage thereto and the load characteristics of the electromechanical system. The applied voltage is sampled electronically to monitor its amplitude level, and microcontroller software and associated circuitry is used to accurately detect application and removal of the applied voltage to the electric motor. While taking into account the simulated acceleration and deceleration of the electric motor, the software model controls a software-based variable speed counter which increments and decrements relative to the direction of motor operation at a rate of speed proportional therewith. The proportional data generated by the variable speed counter correlates with the relative position of the movable component, and can be converted and scaled for appropriate display purposes. The system uses a predetermined reference position of the mechanical component within the electromechanical system to correlate re-synchronization of the software model for the electric motor.

Claims32

Dependent claims

In an electromechanical system having associated load characteristics and an electric motor for driving a mechanical component, a transducerless position determining system for determining the position of said mechanical component, comprising:

(a) means for detecting of application or removal of applied voltage to, and direction of operation of, said electric motor;
(b) applied voltage sampling means connected to said electric motor for determining amplitude level of said applied voltage to said electric motor;
(c) a control means including a motor software model connected to said detection means and said sampling means, said control means being designed to simulate substantially the acceleration, deceleration and velocity characteristics of said electric motor as a function of said applied voltage and load characteristics of said electromechanical system;
and
(d) a variable speed counter being devoid of connection to a positional transducer and being connected in controlled relation to said detection means and said control means so as to increment and decrement at a rate of speed proportional with that of said electric motor and said mechanical component, thereby providing positional data correlating to the relative position of said mechanical component.

2 more elements

A transducerless position determining system for determining the position of a movable component in an electromechanical system, comprising:

(a) an electromechanical system including a movable component driven by an electric motor having a pair of power input terminals that are connectable to a power supply, the direction of operation of said motor being dependent upon the polarity of applied voltage across said pair of input terminals;
(b) a differential input detection means connected to said pair of input terminals of said motor for detecting application or removal of applied voltage thereto and consequent direction of operation of said motor resulting therefrom;
(c) applied voltage sampling means connected to said power supply for monitoring amplitude level of said applied voltage to said pair of power input terminals of said electric motor;
and
(d) transducerless position determining means connected in controlled relation to said detection means for determining the position of said movable component based on data received from said detection means and said sampling means relative to the functional characteristics of said electric motor within said electromechanical system;
(e) said transducerless position determining means including a software model of said electric motor designed to simulate substantially the acceleration, deceleration and velocity characteristics of said electric motor as a function of said applied voltage and load characteristics of said electromechanical system.

3 more elements

A transducerless position determining system for determining the position of a movable component in an electromechanical system, comprising:

(a) an electromechanical system including a movable component driven by an electric motor having at least one power input terminal that is connectable to a power supply, the direction of operation of said motor being dependent upon the applied voltage to each said input terminal;
(b) an input detection means connected to at least one said input terminal for detecting the application or removal of applied voltage thereto and consequent direction of operation of said motor resulting therefrom;
(c) applied voltage sampling means connected to said power supply for periodic sampling of the amplitude level of said applied voltage to said electric motor;
and
(d) a transducerless position determining means connected in controlled relation to said detection means for determining the position of said movable component based on data received from said detection means and said sampling means relative to the functional characteristics of said electric motor within said electromechanical system;
(e) said transducerless position determining means including a software model of said electric motor designed to simulate substantially the acceleration, deceleration and velocity characteristics of said electric motor as a function of the amplitude level of said applied voltage and load characteristics of said electromechanical system.

3 more elements

A transducerless position determining system for determining the position of a movable component in an electromechanical system, comprising:

(a) an electromechanical system including a movable component driven by an electric motor having a pair of power input terminals that are connectable to a power supply, the direction of operation of said motor being dependent upon the polarity of applied voltage across said pair of input terminals;
(b) a differential input detection means connected to said pair of input terminals of said motor for detecting application or removal of applied voltage thereto and consequent direction of operation of said motor resulting therefrom;
(c) applied voltage sampling means connected to said power supply for monitoring amplitude level of said applied voltage to said pair of power input terminals of said electric motor;
(d) a transducerless position determining means connected in controlled relation to said detection means for determining the position of said movable component based on data received from said detection means and said sampling means relative to the functional characteristics of said electric motor within said electromechanical system;
and
(e) voltage shifting means connected to said power input terminals for causing floating generated voltage produced by said electric motor upon removal of power therefrom to undergo an abrupt shift in amplitude level, thereby enabling said detection means to accurately detect removal of said applied voltage from said motor.

3 more elements

A transducerless position determining system for determining the position of a movable component in an electromechanical system, comprising:

(a) an electromechanical system including a movable component driven by an electric motor having first and second power input terminals that are connectable to a power supply, the direction of operation of said motor being dependent upon the polarity of applied voltage across said first and second power input terminals;
(b) a differential input detection means connected to said first and second power input terminals of said motor for detecting application or removal of applied voltage thereto and consequent direction of operation of said motor resulting therefrom;
(c) applied voltage sampling means connected to said power supply for monitoring amplitude level of said applied voltage to said first and second power input terminals of said electric motor;
(d) a transducerless position determining means connected in controlled relation to said detection means for determining the position of said movable component based on data received from said detection means and said sampling means relative to the functional characteristics of said electric motor within said electromechanical system;
and
(e) said differential input detection means being constructed to detect application or removal of applied voltage to each of said first and second power input terminals, and direction of operation of said electric motor, by sensing level transition of said applied voltage across a predetermined threshold voltage level in accordance with the following truth table:
______________________________________ Terminal 1 Terminal 2 Direction ______________________________________ 0 0 Stop 0 1 Reverse 1 0 Forward 1 1 Stop ______________________________________
wherein a "1" indicates detection of applied voltage level above said threshold voltage, and a "0" indicates detection of applied voltage below said threshold voltage level.

5 more elements

Dependencies are inferred from the claim text.

Transducerless position determining system and method for the same

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Transducerless position determining system and method for the same

Life of this patent

Abstract

Claims32