Method and apparatus for process control

Claim 2

Process control apparatus comprising a plurality of control loops for sensing and modifying conditions in the process, each loop having a preset number of control time increments of spacing between control operations on the associated condition; data processing means; and means for selectively connecting said control loops to said data processing means including cyclic counter means operative to change its count by one at the beginning of each increment of control time, means for storing the spacing numbers of time increments between control operations for each loop, means foR storing a phase number within the cycle for each control loop, the phase number for each loop being assigned so that when combined with a particular counter number by an operation sign dependent upon the direction the counter is cycling a result is obtained which is divisible by the spacing number to produce an integer, each loop being assigned a different phase number, means responsive to the passage of each increment of control time for mathematically combining the counter number with the phase number of each loop and dividing each result by the corresponding spacing number for each loop, and means responsive to the occurrence of an integer quotient for connecting the loop having the phase number producing the integer quotient to said data processing means.

Claim 3

Process control apparatus as defined in claim 1 in which said cyclic counter means counts from zero up in its cycle and in which said mathematical combining means includes means for separately subtracting each phase number from the count number in said counter means.

Claim 4

Process control apparatus as defined in claim 1 in which said cyclic counter means counts down toward zero and in which said mathematical combining means includes means for separately adding each phase number to the count number in said counter means.

Claim 5

Process control apparatus as defined in claim 1 which further includes means for producing periodic signals connected to increment said cyclic counter means.

Claim 6

Process control apparatus as defined in claim 4 which further includes sequencing means responsive to said periodic signal means and multiplexer means responsive to said sequencing means for connecting said phase number and said spacing number storage means to said mathematical combining means.

Claim 7

Apparatus for producing glass fibers including a plurality of bushing means for feeding streams of molten glass through feeder orifices formed therein; means for electrically heating each bushing; control loop means for each bushing means for controlling the amount of electrical power supplied to each bushing including means for sensing the temperature of the bushing and power regulating means; data processing means operative to receive a signal from a temperature sensing means of a control loop and to provide a corrective control signal to the power regulating means for that loop; and means for selectively connecting said data processing means to individual control loops including means for providing a repeating counting cycle, means for sequentially mathematically combining each count with a phase number for each control loop representing the assigned phase relation within the cycle of that control loop and for dividing the resulting combination for each loop by the corresponding scan time for that loop to provide a loop quotient, means for checking each loop quotient for a remainder and for providing a selection signal output when there is no remainder, and multiplexer means responsive to said checking means for connecting the temperature sensing means and the power regulating means of the loop having a loop quotient with no remainder to said data processing means.

Claim 8

Apparatus for producing glass fibers including a plurality of bushing means for feeding streams of molten glass through feeder orifices formed therein; means for electrically heating each bushing; control loop means for each bushing means for controlling the amount of electrical power supplied to each bushing including means for sensing the temperature of the bushing and power regulating means; data processing means operative to receive a signal from a temperature sensing means of a control loop and to provide a corrective control signal to the power regulating means for that loop; and means for selectively connecting said data processing means to individual control loops including means for providing a repeating counting cycle, means for sequentially mathematically combining each count with a phase number for each control loop representing the assigned phase relation within the cycle of that control loop and for dividing the resulting combination for each loop by the corresponding scan time for that loop to provide a loop quotient, means for checking each loop quotient for a remainder and for providing a selection signal output when there is no remainder, and multiplexer means responsive to said checking means for connecting the temperature sensing means and the power regulating means of the loop having a loop quotient with no remainder to said data processing means.

Claim 9

Apparatus as defined in claim 6 in which said checking means further provides a sequencing output signal in response to a loop quotient having a remainder, and which further includes sequencing means responsive to selection and sequencing signals for sequentially connecting phase and scan time numbers for each loop to said mathematical combining means.

Claim 10

Apparatus for selecting control operations for a process comprising means for supplying increment signals, cyclic counter means operative to increment one count in response to receipt of an increment signal, means for storing the number of counts between the times of selection for each operation, means for storing the count number of the phase relation of each operation within a cycle with respect to the initial count in said cycle, means responsive to an increment signal for separately mathematically combininG the cycle count with the phase relation count for each operation, means for dividing the resulting combined count for each operation by the count spacing for that operation, and means for checking the quotient for each operation for a remainder and providing an output signal in response to no remainder to select said operation.

Claim 11

Apparatus for selecting control operations for a process comprising means for supplying increment signals, cyclic counter means operative to increment one count in response to receipt of an increment signal, means for storing the number of counts between the times of selection for each operation, means for storing the count number of the phase relation of each operation within a cycle with respect to the initial count in said cycle, means responsive to an increment signal for separately mathematically combininG the cycle count with the phase relation count for each operation, means for dividing the resulting combined count for each operation by the count spacing for that operation, and means for checking the quotient for each operation for a remainder and providing an output signal in response to no remainder to select said operation.

Claim 12

In apparatus for a glass melting and fiber forming process having a plurality of conditions being controlled, each condition having a number of control time increments between control operations designated as scan time which is dependent upon the response time for changes to be effected in the condition being controlled and the response time of the control loop performing the control operation so that control of each condition is not possible on each increment of control time, means for supplying clock signals for each increment of control time, cyclic counter means operative to change its count by one in response to receipt of a clock signal, means for storing the scan time number for each of said conditions being controlled, means for storing a phase number for each of said conditions being controlled, each phase number representing the phase difference between a zero count in the counter and the count when a control operation for each condition is to be performed, means responsive to each clock signal for separately mathematically combining the count number in the counter with each of the stored phase numbers by a mathematical operation sign dependent upon the direction in which the count in said cyclic counter means is proceeding, means for dividing each of the mathematically combined numbers by the corresponding scan time number for each phase number of the combined number, and means for checking each resulting quotient for a remainder and for providing a selection signal in response to finding an integer quotient.

Claim 13

In apparatus for a glass melting and fiber forming process having a plurality of conditions being controlled, each condition having a number of control time increments between control operations designated as scan time which is dependent upon the response time for changes to be effected in the condition being controlled and the response time of the control loop performing the control operation so that control of each condition is not possible on each increment of control time, means for supplying clock signals for each increment of control time, cyclic counter means operative to change its count by one in response to receipt of a clock signal, means for storing the scan time number for each of said conditions being controlled, means for storing a phase number for each of said conditions being controlled, each phase number representing the phase difference between a zero count in the counter and the count when a control operation for each condition is to be performed, means responsive to each clock signal for separately mathematically combining the count number in the counter with each of the stored phase numbers by a mathematical operation sign dependent upon the direction in which the count in said cyclic counter means is proceeding, means for dividing each of the mathematically combined numbers by the corresponding scan time number for each phase number of the combined number, and means for checking each resulting quotient for a remainder and for providing a selection signal in response to finding an integer quotient.

Claim 16

A method as defined in claim 10 which further includes selecting the occurrence of said control functions comprising the steps of separately mathematically combining the sequence number of each time increment of said cycle as the cycle progresses with the phase number of each control function in the manner of the calculation step and dividing the resulting number by the corresponding scan time number for each control function, and checking the resulting quotients for an integer, the occurrence of an integer signalling the occurrence of a control function at that time increment in said cycle.

Claim 19

In establishing the occurrence of a plurality of control functions of a process in a repeating cycle of time increments designated in sequence from the initial increment in the cycle, where each function has a preset number of said time increments between occurrences designated as scan time for that function, and where the cycle has the same number as or a multiple of increments in the scan time for the least frequently occurring of the control functions, the system for selecting control functions at a time increment comprising means for producing a cycle count designation at each increment in the cycle; means for producing a phase designation at each increment in the cycle for each function, representing the time increment relation of each said function within the cycle with respect to the initial time increment in the cycle; means for separately mathematically combining the cycle count designation with the phase designation of each function at each time increment in the cycle; means for dividing each of the resulting combined designations for each function by the scan time designation for that function; and means for checking the quotient for each division for a remainder and selecting a function having a predetermined remainder for operation at that time increment of said cycle.

Claim 20

In establishing the occurrence of a plurality of control functions of a process in a repeating cycle of time increments designated in sequence from the initial increment in the cycle, where each function has a preset number of said time increments between occurrences designated as scan time for that function, and where the cycle has the same number as or a multiple of increments in the scan time for the least frequently occurring of the control functions, the system for selecting control functions at a time increment comprising means for producing a cycle count designation at each increment in the cycle; means for producing a phase designation at each increment in the cycle for each function, representing the time increment relation of each said function within the cycle with respect to the initial time increment in the cycle; means for separately mathematically combining the cycle count designation with the phase designation of each function at each time increment in the cycle; means for dividing each of the resulting combined designations for each function by the scan time designation for that function; and means for checking the quotient for each division for a remainder and selecting a function having a predetermined remainder for operation at that time increment of said cycle.

Claim 21

In establishing the occurrence of each of a plurality of control functions of a process at its own time increment in a repeating cycle having time increments numbered in sequence, where each function has a preset number of increments between occurrences designated as a scan time for the function, where the number of time increments in the cycle is the same as or a multiple of the number of increments in the scan time for the least frequently occurring of the control junctions, and where each function has a phase number designating the time increment of its occurrence within the cycle with respect to an initial time increment, the system for selecting control functions at different time increments in the cycle comprising means for separately mathematically combining the sequence number of each time increment of said cycle as the cycle progresses with the phase number of each control function in the equation

Claim 22

In establishing the occurrence of each of a plurality of control functions of a process at its own time increment in a repeating cycle having time increments numbered in sequence, where each function has a preset number of increments between occurrences designated as a scan time for the function, where the number of time increments in the cycle is the same as or a multiple of the number of increments in the scan time for the least frequently occurring of the control junctions, and where each function has a phase number designating the time increment of its occurrence within the cycle with respect to an initial time increment, the system for selecting control functions at different time increments in the cycle comprising means for separately mathematically combining the sequence number of each time increment of said cycle as the cycle progresses with the phase number of each control function in the equation

Claim 23

The system as defined in claim 14 in which the initial increment in the repeating cycle is numbered zero, the next successive increment is numbered one, and the remaining increments are numbered in arithmetic progression.

Claim 28

The method as defined in claim 17 which further includes designating the mathematical operation sign for combining the sequence number with the phase number as positive when the increments in the cyclic count are enumerated and as negative when the increments in the cyclic count are enumerated in sequence down toward the zero increment, and further designating the phase number sign as positive when the phase is expressed as the number of increments occurring in the cyclic count before arriving at the zero increment in the direction of enumeration and as negative when the phase is expressed as the number of increments occurring in the cyclic count after arriving at the zero increment in the direction of enumeration.