Position control system with plural signal transmission through common inductive device

Claim 2

In apparatus having first and second members movable independently to different positions along a common path by drive from first and second respective motors, the combination comprising a. a resolver type device including a first part disposed stationarily along said path and second and third parts mounted respectively on said first and second members to move along and in closely spaced relation to the first part as said members move, b. said first part having an output winding inductively coupled to first and second input windings respectively disposed on said second and third parts, c. means for exciting said first input windings with alternating voltage of a first predetermined frequency and which in amplitude represents the analog of a commanded position of the first member, d. means for exciting said second input windings with alternating voltage of a second predetermined frequency and which in amplitude represents the analog of a commanded position of the second member, e. means for exciting said first input windings with alternating voltage of a third predetermined frequency superimposed upon the voltage of said first frequency, f. means coupled to receive the output signal induced in said output winding and responsive to the first frequency component therein for producing a first error signal indicative of the difference between the commanded and actual positions of the first member, g. means coupled to receive the output signal induced in said output winding and responsive to the second frequency component therein for producing a second error signal indicative of the difference between the commanded and actual positions of the second member, h. means coupled to receive the output signal induced in said output winding and responsive to the third frequency component therein for producing an auxiliary signal, and i. detector apparatus coupled to receive said auxiliary signal and including means responsive to substantial reduction in the amplitude thereof for indicating a malfunction.

Claim 3

In apparatus having first and second members movable independently to different positions along a common path by drive from first and second respective servomotors, the combination comprising a. a resolver type device including a first part disposed stationarily along said path and second and third parts mounted respectively on said first and second members to move along and in closely spaced relation to the first part as said members move, b. said first part having an output winding inductively coupled to first and second input windings respectively disposed on said second and third parts, c. means for exciting said first input windings with alternating voltage of a first predetermined frequency and which in amplitude represents the analog of a commanded position of the first member, d. means for exciting said second input windings with alternating voltage of a second predetermined frequency and which in amplitude represents the analog of a commanded position of the second member, e. means for exciting said first input windings with alternating voltage of a third predetermined frequency superimposed upon the voltage of said first frequency, f. means coupled to receive the output signal induced in said output winding and responsive to the first frequency component therein for producing a first error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the first member, g. means coupled to receive the output signal induced in said output winding and responsive to the second frequency component therein for producing a second error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the second member, h. means coupled to receive the output signal induced in said output winding and responsive to the third frequency component therein for producing an auxiliary signal, i. means for energizing the first motor in accordance with said first error signal to drive the first member to an actual position in which said first frequency component in said output signal is reduced substantially to zero, j. means for energizing the second motor in accordance with said second error signal to drive the second mEmber to an actual position in which said second frequency component in said output signal is reduced substantially to zero, and k. means responsive to the absence of said auxiliary signal for indicating a malfunction or a lack of reliability in the resolver type device or its associated components.

Claim 4

In apparatus having first and second members movable independently to different positions along a common path by drive from first and second respective servomotors, the combination comprising a. a resolver type device including a first part disposed stationarily along said path and second and third parts mounted respectively on said first and second members to move along and in closely spaced relation to the first part as said members move, b. said first part having an output winding inductively coupled to first and second input windings respectively disposed on said second and third parts, c. means for exciting said first input windings with alternating voltage of a first predetermined frequency and which in amplitude represents the analog of a commanded position of the first member, d. means for exciting said second input windings with alternating voltage of a second predetermined frequency and which in amplitude represents the analog of a commanded position of the second member, e. means for exciting said first input windings with alternating voltage of a third predetermined frequency superimposed upon the voltage of said first frequency, f. means coupled to receive the output signal induced in said output winding and responsive to the first frequency component therein for producing a first error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the first member, g. means coupled to receive the output signal induced in said output winding and responsive to the second frequency component therein for producing a second error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the second member, h. means coupled to receive the output signal induced in said output winding and responsive to the third frequency component therein for producing an auxiliary signal, i. means for energizing the first motor in accordance with said first error signal to drive the first member to an actual position in which said first frequency component in said output signal is reduced substantially to zero, j. means for energizing the second motor in accordance with said second error signal to drive the second mEmber to an actual position in which said second frequency component in said output signal is reduced substantially to zero, and k. means responsive to the absence of said auxiliary signal for indicating a malfunction or a lack of reliability in the resolver type device or its associated components.

Claim 5

The combination set forth in claim 2 further characterized in that said resolver type device is a ''''linear Inductosyn'''' device in which said first part is an elongated ''''scale'''' and said second and third parts are ''''sliders'''' respectively mounted on said first and second members with each slider having a sin and cos input winding; and wherein said alternating voltage of first predetermined frequency includes two ac. voltages related in amplitude to the sine and cosine of the commanded position of the first member; said alternating voltage of second predetermined frequency includes two ac. voltages related in amplitude to the sine and cosine of the commanded position of the second member; and wherein said alternating voltage of third predetermined frequency includes two ac. voltages of constant and equal amplitude separated in phase by 90; whereby in the absence of any malfunction the auxiliary signal remains finite and substantially constant in magnitude as said first and second error signals take on null or zero values.

Claim 6

In apparatus having first and second members movable independently to different positions along a common path by drive from first and second respective servomotors, the combination comprising a. a resolver type device including a first part disposed stationarily along said path and second and third parts mounted respectively on said first and second members to move along and in closely spaced relation to the first part as said members move, b. said first part having an output winding inductively coupled to first and second input windings respectively disposed on said second and third parts, c. means for exciting said first input windings with alternating voltage of a first predetermined frequency and which in amplitude represents the analog of a changeable commanded position of the first member, d. means for exciting said second input windings with alternating voltage of a second predetermined frequency and which in amplitude represents the analog of a changeable commanded position of the second member, e. means coupled to receive the output signal induced in said output winding and responsive to the first frequency component therein for producing a first error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the first member, f. means coupled to receive the output signal induced in said output winding and responsive to the second frequency component therein for producing a second error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the first member, g. means for energizing the first servomotor in accordance with said first error signal to drive the first member to an actual position which agrees with its commanded position, and h. means for energizing the second servomotor in accordance with said second error signal to drive the second member to an actual position which agrees with its commanded position.

Claim 7

In apparatus having first and second members movable independently to different positions along a common path by drive from first and second respective servomotors, the combination comprising a. a resolver type device including a first part disposed stationarily along said path and second and third parts mounted respectively on said first and second members to move along and in closely spaced relation to the first part as said members move, b. said first part having an output winding inductively coupled to first and second input windings respectively disposed on said second and third parts, c. means for exciting said first input windings with alternating voltage of a first predetermined frequency and which in amplitude represents the analog of a changeable commanded position of the first member, d. means for exciting said second input windings with alternating voltage of a second predetermined frequency and which in amplitude represents the analog of a changeable commanded position of the second member, e. means coupled to receive the output signal induced in said output winding and responsive to the first frequency component therein for producing a first error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the first member, f. means coupled to receive the output signal induced in said output winding and responsive to the second frequency component therein for producing a second error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of the first member, g. means for energizing the first servomotor in accordance with said first error signal to drive the first member to an actual position which agrees with its commanded position, and h. means for energizing the second servomotor in accordance with said second error signal to drive the second member to an actual position which agrees with its commanded position.

Claim 8

In apparatus having a member movable to different positions along a predetermined path by drive from a motor, the combination comprising a. a resolver type device including a first stationary part and a second part mechanically coupled to the member to move in accordance with the member''s displacements but always remaining in closely spaced proximity to the first part, b. said first part having an output winding inductively coupled to input windings disposed on said second part, c. means for applying to said input windings alternating voltage of a first predetermined frequency which in amplitude represents a Numerically commanded position, d. means for exciting said input windings with alternating voltage of a second predetermined frequency superimposed upon the voltage of the first frequency, e. means connected to said output winding and responsive only to the first frequency component of the induced output signal for producing an error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of said member, f. means connected to said output winding and responsive to the second frequency component of the induced output signal for producing an auxiliary monitoring signal, and g. means coupled to receive said monitor signal and responsive to a substantial reduction of such signal for indicating a malfunction.

Claim 9

In apparatus having a member movable to different positions along a predetermined path by drive from a motor, the combination comprising a. a resolver type device including a first stationary part and a second part mechanically coupled to the member to move in accordance with the member''s displacements but always remaining in closely spaced proximity to the first part, b. said first part having an output winding inductively coupled to input windings disposed on said second part, c. means for applying to said input windings alternating voltage of a first predetermined frequency which in amplitude represents a Numerically commanded position, d. means for exciting said input windings with alternating voltage of a second predetermined frequency superimposed upon the voltage of the first frequency, e. means connected to said output winding and responsive only to the first frequency component of the induced output signal for producing an error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of said member, f. means connected to said output winding and responsive to the second frequency component of the induced output signal for producing an auxiliary monitoring signal, and g. means coupled to receive said monitor signal and responsive to a substantial reduction of such signal for indicating a malfunction.

Claim 10

In apparatus having a member movable to different positions along a predetermined path by drive from a servomotor, the combination comprising a. a resolver type device including a first stationary part and a second part mechanically coupled to the member to move in accordance with the member''s displacements but always remaining in closely spaced proximity to the first part, b. said first part having an output winding inductively coupled to sin/cos input windings disposed on said second part, c. means for applying to said sin/cos input windings alternating voltages of a first predetermined frequency which in amplitude are proportional to the sine and cosine of a numerically commanded position expressed as an angle where 360* represents a predetermined repeating span, d. means for exciting said sin/cos input windings with alternating voltages of a second predetermined frequency superimposed upon those voltages of the first frequency, e. means connected to said output winding and responsive only to the first frequency component of the induced output signal for producing an error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of said member, f. means connected to said output winding and responsive to the second frequency component of the induced output signal for producing a monitor signal, g. means for energizing said motor in accordance with said error signal to drive the member to an actual position in which said first frequency component in said output signal is reduced substantially to zero, and h. a detector coupled to receive said monitor signal and including means responsive to a substantial reduction of such signal for indicating a malfunction.

Claim 11

In apparatus having a member movable to different positions along a predetermined path by drive from a servomotor, the combination comprising a. a resolver type device including a first stationary part and a second part mechanically coupled to the member to move in accordance with the member''s displacements but always remaining in closely spaced proximity to the first part, b. said first part having an output winding inductively coupled to sin/cos input windings disposed on said second part, c. means for applying to said sin/cos input windings alternating voltages of a first predetermined frequency which in amplitude are proportional to the sine and cosine of a numerically commanded position expressed as an angle where 360* represents a predetermined repeating span, d. means for exciting said sin/cos input windings with alternating voltages of a second predetermined frequency superimposed upon those voltages of the first frequency, e. means connected to said output winding and responsive only to the first frequency component of the induced output signal for producing an error signal which varies in magnitude and polarity according to the difference between the commanded and actual positions of said member, f. means connected to said output winding and responsive to the second frequency component of the induced output signal for producing a monitor signal, g. means for energizing said motor in accordance with said error signal to drive the member to an actual position in which said first frequency component in said output signal is reduced substantially to zero, and h. a detector coupled to receive said monitor signal and including means responsive to a substantial reduction of such signal for indicating a malfunction.

Claim 12

The combination set forth in claim 6 further characterized by means for making said alternating voltages of said second frequency have a phase quadrature relation.