US3904338A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method for controlling a machine continuously feeding a sheet to intermittently activated station
Assignee: Industrial Nucleonics Corp
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Filing: 1973-12-28
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Granted: 1975-09-09
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Expires: 1993-12-28
Abstract
Abstract An extruder continuously forms a sheet that is intermittently supplied to an intermittently activated, in-line processing station, e.g., a thermoformer. The sheet is supplied to the processing station via a variable accumulator that is adapted to have a rest state immediately prior to the sheet being supplied to the processing station. The extruder includes a screw for feeding material to sheet forming dies at a mouth of the extruder, as well as rolls for taking the sheet material away from the extruder mouth. The rest state time is measured to derive an indication of the take-away speed of the sheet from the mouth relative to the speed with which the sheet moves through the intermittently activated processing station. The activation rate of the processing station is measured, as is the thickness of the sheet after it has reached a set state, prior to passing through the accumulator. In response to the three measurements, the screw and line speeds are controlled so that the sheet thickness is maintained approximately at a setpoint value, and sufficient material is always available to the processing station, and excess material is prevented from piling up at the accumulator.
Inventors
- 👤 Maris Straumanis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:55
CPC Classifications
G; G05; G05D; G05D5/00; G05D5/02; G05D5/03; B; B29; B29C; B29C48/00; B29C48/001; B29C48/25; B29C48/92; B29C2948/00; B29C2948/92; B29C2948/92009; B29C2948/92085; B29C2948/92114; B29C2948/92152; B29C2948/92323; B29C2948/92438; B29C2948/92504; B29C2948/9258; B29C2948/9279; B29C2948/92819; B29C2948/92933; B29C48/0011; B29C48/0017; B29C48/03; B29C48/07; B29C48/08
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
85 words
A device for measuring the speed of a sheet continuously derived from a machine relative to the speed at which the sheet is fed through an intermittently activated processing station in line with the machine comprising a variable sheet accumulator between the machine and sheet, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the processing station, and means for measuring the duration of the rest state.
Claim 2
Independent Claim
85 words
A device for measuring the speed of a sheet continuously derived from a machine relative to the speed at which the sheet is fed through an intermittently activated processing station in line with the machine comprising a variable sheet accumulator between the machine and sheet, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the processing station, and means for measuring the duration of the rest state.
Claim 3
Dependent Claim
96 words
Apparatus for controlling the feed rate of a sheet continuously derived from a supply source and intermittently fed to an intermittently activated, in-line processing station via a sheet accumulator between the source and the station, said accumulator including a dancer roll, comprising means for controlling the intermittent feed of the sheet to the station so that the dancer roll assumes a rest state each tIme the station is activated, means for measuring the rest state duration, and means for deriving a control signal for the continuous feed rate in response to the measured rest state duration.
Claim 4
Dependent Claim
96 words
Apparatus for controlling the feed rate of a sheet continuously derived from a supply source and intermittently fed to an intermittently activated, in-line processing station via a sheet accumulator between the source and the station, said accumulator including a dancer roll, comprising means for controlling the intermittent feed of the sheet to the station so that the dancer roll assumes a rest state each tIme the station is activated, means for measuring the rest state duration, and means for deriving a control signal for the continuous feed rate in response to the measured rest state duration.
Claim 5
Independent Claim
151 words
A system for controlling a machine continuously deriving a sheet that is fed to an intermittently activated, in-line processing station comprising means for measuring the speed of the sheet derived from the machine relative to the speed of the sheet in the processing station, said means for measuring including a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, means for measuring the duration of the rest state, means for deriving a first indication of whether the rest period is constant or changing and for indicating the direction of change and for deriving a second indication of the magnitude of the relative speed, and means responsive to the first and second indications for deriving a control signal for the sheet feed rate.
Claim 6
Independent Claim
151 words
A system for controlling a machine continuously deriving a sheet that is fed to an intermittently activated, in-line processing station comprising means for measuring the speed of the sheet derived from the machine relative to the speed of the sheet in the processing station, said means for measuring including a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, means for measuring the duration of the rest state, means for deriving a first indication of whether the rest period is constant or changing and for indicating the direction of change and for deriving a second indication of the magnitude of the relative speed, and means responsive to the first and second indications for deriving a control signal for the sheet feed rate.
Claim 7
Dependent Claim
29 words
The system of claim 3 wherein the control signal deriving means includes means responsive to the indications for selectively increasing and decreasing the control signal magnitude by fixed amounts.
Claim 8
Dependent Claim
45 words
The system of claim 4 wherein the control signal deriving means includes means for measuring the speed of the continuously derived sheet, and means responsive to the indications for selectively controlling the magnitude of the control signal as a function of the measured sheet speed.
Claim 9
Dependent Claim
55 words
The system of claim 4 wherein the control signal deriving means includes means for measuring the speed of the continuously derived sheet, and means responsive to the indications for selectively controlling the magnitude of the control signal in response to the magnitude of the measured sheet speed and the rate of change of rest period.
Claim 10
Dependent Claim
117 words
The system of claim 6 further including means for deriving signals indicative of established predetermined boundaries for the relative speed values, means responsive to the signals indicative of the boundaries and the second indication for deriving a further indication of between which of the boundaries the measured relative value lies, and means responsive to the first and further indications for selecting whether the control signal has (a) no effect on the sheet feed rate, (b) causes the sheet feed rate to increase or decrease by a fixed amount, or (c) causes the sheet feed rate to increase or decrease by an amount indicative of the measured sheet speed and the rate of change of measured sheet speed.
Claim 11
Dependent Claim
98 words
The system of claim 7 wherein the means for deriving the further indication includes means for signalling an excess sheet alarm condition in response to the first indication indicating that the rest period is increasing and that the second indication indicating that the relative sheet speed is above a predetermined value, and means responsive to the alarm condition for selecting a control signal amplitude that causes the sheet feed rate to decrease by an amount proportional to the product of measured sheet speed and the second indication or the rate of change of sheet speed, whichever is greater.
Claim 12
Dependent Claim
45 words
The system of claim 3 wherein the control signal deriving means includes means for measuring the speed of the continuously derived sheet, and means responsive to the indications for selectively controlling the magnitude of the control signal as a function of the measured sheet speed.
Claim 13
Dependent Claim
105 words
The system of claim 3 wherein the control signal deriving means includes means for measuring the speed of the continuously derived sheet, means for signalling an excess sheet alarm condition in response to the first indication indicating that the rest period is increasing and the the second indication indicating that the relative sheet speed is above a predetermined value, and means responsive to the alarm condition for selecting a control signal amplitUde that causes the sheet feed rate to decrease by an amount proportional to the product of measured sheet speed and the first indication or a predetermined constant, whichever is smaller in absolute value.
Claim 14
Independent Claim
241 words
A system for controlling an extruder continuously deriving a sheet that is intermittently supplied to an intermittently activated, in-line processing station via a variable accumulator, said accumulator adapted to have a rest state immediately prior to the sheet being supplied to the processing station, said extruder including means for feeding material to a sheet former and means for taking sheet material away from the former, the sheet being in a relatively soft state as it is taken away from the former so that the speed with which the sheet is taken away from the former affects the sheet thickness, the sheet being in a relatively set state as it passes through the accumulator so that the speed of the sheet as it moves through the accumulator has no substantial effect on sheet thickness, comprising means for measuring the rest state time to derive a first signal indicative of the take-away speed relative to the speed with which the sheet moves through the processing station, means for measuring the activation rate of the processing station to derive a second signal indicative of the activation rate, means for measuring the thickness of the sheet in the set state to derive a third signal indicative of the measured thickness, and means responsive to said first, second and third signals for deriving control signals for the speed of the means for feeding and the means for taking away so as to control the take-away speed.
Claim 15
Independent Claim
241 words
A system for controlling an extruder continuously deriving a sheet that is intermittently supplied to an intermittently activated, in-line processing station via a variable accumulator, said accumulator adapted to have a rest state immediately prior to the sheet being supplied to the processing station, said extruder including means for feeding material to a sheet former and means for taking sheet material away from the former, the sheet being in a relatively soft state as it is taken away from the former so that the speed with which the sheet is taken away from the former affects the sheet thickness, the sheet being in a relatively set state as it passes through the accumulator so that the speed of the sheet as it moves through the accumulator has no substantial effect on sheet thickness, comprising means for measuring the rest state time to derive a first signal indicative of the take-away speed relative to the speed with which the sheet moves through the processing station, means for measuring the activation rate of the processing station to derive a second signal indicative of the activation rate, means for measuring the thickness of the sheet in the set state to derive a third signal indicative of the measured thickness, and means responsive to said first, second and third signals for deriving control signals for the speed of the means for feeding and the means for taking away so as to control the take-away speed.
Claim 16
Dependent Claim
113 words
The system of claim 11 wherein the control signal deriving means includes a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, means for measuring the duration of the rest state, means for deriving a first indication of whether the rest period is constant or changing and for indicating the direction of change and for deriving a second indication of the magnitude of the relative speed, and means responsive to the first and second indications for deriving a control signal for the take-away speed.
Claim 17
Independent Claim
386 words
A system for controlling a machine that continuously derives a sheet and feeds it to an in-line intermittently activated processing station where the sheet is in a set state, the machine including means for controlling the feed rate of material forming the sheet, the sheet thickness being affected by the sheet and material feed rates, the sheet being intermittently advanced for the machine to the station via a variable accumulator, comprising means for measuring the relative speeds of the sheet derived from the machine and in passing through the station, means for measuring the thickness of the sheet, and means responsive to both of the measuring means for deriving control signals for the feed rate of the sheet and the feed rate of the material, said means for deriving control signals including means for measuring the activation rate of the station, means comparing the measured activation rate with a setpoint value therefor for deriving first and second indications respectively indicative of the measured rate exceeding and being less than the setpoint value therefor, means responsive to the first indication for deriving a first control signal for the speed of the sheet derived from the machine, said first control signal having a magnitude dependent on the relative values of the measured rate and the setpoint value therefor, and means responsive to the second indication for deriving a second control signal for the speed of the sheet derived from the machine, said second control signal having a magnitude dependent on the speed of the sheet as it is derived from the machine relative to the speed of the sheet at the station, said means for deriving control signals while the second indication is being derived including a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, means for measuring the duration of the rest state, means for deriving a third indication of whether the rest period is constant or changing and for indicating the direction of change and for deriving a fourth indication of the magnitude of the relative speed, and means responsive to the third and fourth indications for deriving a control signal for the sheet feed rate.
Claim 18
Independent Claim
386 words
A system for controlling a machine that continuously derives a sheet and feeds it to an in-line intermittently activated processing station where the sheet is in a set state, the machine including means for controlling the feed rate of material forming the sheet, the sheet thickness being affected by the sheet and material feed rates, the sheet being intermittently advanced for the machine to the station via a variable accumulator, comprising means for measuring the relative speeds of the sheet derived from the machine and in passing through the station, means for measuring the thickness of the sheet, and means responsive to both of the measuring means for deriving control signals for the feed rate of the sheet and the feed rate of the material, said means for deriving control signals including means for measuring the activation rate of the station, means comparing the measured activation rate with a setpoint value therefor for deriving first and second indications respectively indicative of the measured rate exceeding and being less than the setpoint value therefor, means responsive to the first indication for deriving a first control signal for the speed of the sheet derived from the machine, said first control signal having a magnitude dependent on the relative values of the measured rate and the setpoint value therefor, and means responsive to the second indication for deriving a second control signal for the speed of the sheet derived from the machine, said second control signal having a magnitude dependent on the speed of the sheet as it is derived from the machine relative to the speed of the sheet at the station, said means for deriving control signals while the second indication is being derived including a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, means for measuring the duration of the rest state, means for deriving a third indication of whether the rest period is constant or changing and for indicating the direction of change and for deriving a fourth indication of the magnitude of the relative speed, and means responsive to the third and fourth indications for deriving a control signal for the sheet feed rate.
Claim 19
Independent Claim
233 words
A system for controlling a machine that continuously derives a sheet and feeds it to an in-line intermittently activated processing station where the sheet is in a set state, the machine including means for controlling the feed rate of material forming the sheet, the sheet thickness being affected by the sheet and material feed rates, the sheet being intermittently advanced from the machine to the station via a variable accumulator, comprising means for measuring the relative speeds of the sheet derived from the machine and in passing through the station, means for measuring the thickness of the sheet, and means responsive to both of the measuring means for deriving control signals for the feed rate of the sheet and the feed rate of the material, said control signal deriving means including a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, means for measuring the duration of the rest state, means for deriving a first indication of whether the rest period is constant or changing and for indicating the direction of change and for deriving a second indication of the magnitude of the relative speed, and means responsive to the first and second indications for deriving a control signal for the sheet feed rate.
Claim 20
Independent Claim
233 words
A system for controlling a machine that continuously derives a sheet and feeds it to an in-line intermittently activated processing station where the sheet is in a set state, the machine including means for controlling the feed rate of material forming the sheet, the sheet thickness being affected by the sheet and material feed rates, the sheet being intermittently advanced from the machine to the station via a variable accumulator, comprising means for measuring the relative speeds of the sheet derived from the machine and in passing through the station, means for measuring the thickness of the sheet, and means responsive to both of the measuring means for deriving control signals for the feed rate of the sheet and the feed rate of the material, said control signal deriving means including a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, means for measuring the duration of the rest state, means for deriving a first indication of whether the rest period is constant or changing and for indicating the direction of change and for deriving a second indication of the magnitude of the relative speed, and means responsive to the first and second indications for deriving a control signal for the sheet feed rate.
Claim 21
Independent Claim
82 words
A method of controlling the feed rate of a sheet continuously derived from a supply source and intermittently fed to an intermittently activated, in-line processing station via a sheet accumulator between the source and the station, said accumulator including a dancer roll, comprising controlling the intermittent feed of the sheet to the station so that the dancer roll assumes a rest state each time the station is activated, and controlling the continuous feed rate in response to the measured rest state duration.
Claim 22
Independent Claim
82 words
A method of controlling the feed rate of a sheet continuously derived from a supply source and intermittently fed to an intermittently activated, in-line processing station via a sheet accumulator between the source and the station, said accumulator including a dancer roll, comprising controlling the intermittent feed of the sheet to the station so that the dancer roll assumes a rest state each time the station is activated, and controlling the continuous feed rate in response to the measured rest state duration.
Claim 23
Dependent Claim
39 words
The method of claim 15 wherein the continuous feed rate is controlled so that the dancer roll rest state duration lies in a predetermined range of values greater than zero such that excess sheet is derived from the source.
Claim 24
Independent Claim
128 words
A method of controlling a machine continuously deriving a sheet that is fed to an intermittently activated, in-line processing station via a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, comprising measuring the duration of the rest period to derive a first indication of the speed of the sheet derived from the machine relative to the speed of the sheet in the processing station, deriving a second indication of whether the rest period is constant or changing and for indicating the direction of change, and controlling the sheet feed rate in response to the first and second indications.
Claim 25
Independent Claim
128 words
A method of controlling a machine continuously deriving a sheet that is fed to an intermittently activated, in-line processing station via a variable sheet accumulator between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, comprising measuring the duration of the rest period to derive a first indication of the speed of the sheet derived from the machine relative to the speed of the sheet in the processing station, deriving a second indication of whether the rest period is constant or changing and for indicating the direction of change, and controlling the sheet feed rate in response to the first and second indications.
Claim 26
Dependent Claim
37 words
The method of claim 17 further including the step of measuring the speed of the continuously derived sheet, and controlling the sheet feed rate as a function of the measured sheet speed in response to the indications.
Claim 27
Dependent Claim
110 words
The method of claim 17 further including the steps of establishing predetermined boundaries for the relative speed values, responding to the indications of the boundaries And the first indication to derive a further indication of between which of the boundaries the measured relative value lies, responding to the second and further indications for selecting whether the control signal has (a) no effect on the sheet feed rate, (b) causes the sheet feed rate to increase or decrease by a fixed amount, or (c) causes the sheet feed rate to increase or decrease by an amount indicative of the measured sheet speed and the rate of change of measured sheet speed.
Claim 28
Independent Claim
130 words
A method of controlling a machine that continuously derives a sheet and feeds it to an in-line intermittently activated processing station where the sheet is in a set state, the machine including means for controlling the feed rate of material forming the sheet, the sheet thickness being affected by the sheet and material feed rates, the sheet being intermittently advanced from the machine to the station via a variable accumulator, comprising measuring the relative speeds of the sheet derived from the machine and in passing through the station, measuring the thickness of the sheet, and maintaining the thickness substantially constant despite changes in the sheet feed rate by controlling the feed rate of the sheet concomitantly with the feed rate of the material in response to both of the measurements.
Claim 29
Independent Claim
130 words
A method of controlling a machine that continuously derives a sheet and feeds it to an in-line intermittently activated processing station where the sheet is in a set state, the machine including means for controlling the feed rate of material forming the sheet, the sheet thickness being affected by the sheet and material feed rates, the sheet being intermittently advanced from the machine to the station via a variable accumulator, comprising measuring the relative speeds of the sheet derived from the machine and in passing through the station, measuring the thickness of the sheet, and maintaining the thickness substantially constant despite changes in the sheet feed rate by controlling the feed rate of the sheet concomitantly with the feed rate of the material in response to both of the measurements.
Claim 30
Dependent Claim
126 words
The method of claim 20 wherein the sheet feed rate is controlled by measuring the activation rate of the station, comparing the measured activation rate with a setpoint value therefor, deriving first and second indications respectively indicative of the measured rate exceeding and being less than the setpoint value therefor, in response to the first indication increasing the speed of the sheet derived from the machine by an amount dependent on the relative values of the measured rate and the setpoint value therefor, in response to the second indication controlling the speed of the sheet derived from the machine by an amount dependent on the speed of the sheet as it is derived from the machine relative to the speed of the sheet at the station.
Claim 31
Dependent Claim
119 words
The method of claim 21 wherein a variable sheet accumulator is provided between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior to the sheet being supplied to the station, the sheet feed rate being controlled while the second indication is derived by measuring the rest period duration, deriving a third indication of whether the rest period duration is constant or changing and for indicating the direction of change, in response to the measured rest period duration, deriving a fourth indication of the magnitude of the relative speed, and controlling the sheet feed rate in response to the third and fourth indications.
Claim 32
Dependent Claim
111 words
The method of claim 20 wherein a variable sheet accumulator is provided between the machine and the station, the two speeds and the accumulator being such that the accumulator is normally adapted to have a rest state immediately prior the sheet being supplied to the station, the sheet feed rate being controlled by: measuring the rest period duration, deriving a first indication of whether the rest period is constant or changing and for indicating the direction of change, in response to the measured rest period duration, deriving a second indication of the magnitude of the relative speed, and controlling the sheet feed rate in response to the first and second indications.
Claim 33
Independent Claim
239 words
A method of controlling an extruder continuously deriving a sheet that is intermittently supplied to an intermittently activated, in-line processing station via a variable accumulator, said accumulator adapted to have a rest state immediately prior to the sheet being supplied to the processing station, said extruder including means for feeding material to a sheet former and means for taking sheet material away from the former, the sheet being in a relatively soft state as it is taken away from the former so that the speed with which the sheet Is taken away from the former affects the sheet thickness, the sheet being in a relatively set state as it passes through the accumulator so that the speed of the sheet as it moves through the accumulator has no substantial effect on sheet thickness, comprising measuring the rest state time to derive a first signal indicative of the take-away speed relative to the speed with which the sheet moves through the processing station, measuring the activation rate of the processing station to derive a second signal indicative of the activation rate, measuring the thickness of the sheet in the set state to derive a third signal indicative of the measured thickness, and concomitantly controlling the speed of the means for feeding and the means for taking away so as to control the take-away speed and maintain the sheet thickness substantially constant by responding to said first, second and third signals.
Claim 34
Independent Claim
239 words
A method of controlling an extruder continuously deriving a sheet that is intermittently supplied to an intermittently activated, in-line processing station via a variable accumulator, said accumulator adapted to have a rest state immediately prior to the sheet being supplied to the processing station, said extruder including means for feeding material to a sheet former and means for taking sheet material away from the former, the sheet being in a relatively soft state as it is taken away from the former so that the speed with which the sheet Is taken away from the former affects the sheet thickness, the sheet being in a relatively set state as it passes through the accumulator so that the speed of the sheet as it moves through the accumulator has no substantial effect on sheet thickness, comprising measuring the rest state time to derive a first signal indicative of the take-away speed relative to the speed with which the sheet moves through the processing station, measuring the activation rate of the processing station to derive a second signal indicative of the activation rate, measuring the thickness of the sheet in the set state to derive a third signal indicative of the measured thickness, and concomitantly controlling the speed of the means for feeding and the means for taking away so as to control the take-away speed and maintain the sheet thickness substantially constant by responding to said first, second and third signals.
Claim 35
Dependent Claim
61 words
The method of claim 24 wherein the control signal for the take-away speed is derived by deriving a first indication of whether the rest period is constant or changing and for indicating the direction of change, deriving a second indication of the magnitude of the relative speed, and controlling the sheet take-away speed in response to the first and second indications.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-08 | 1979-03-10 | 1979-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-08 | 1983-03-10 | 1983-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-08 | 1987-03-10 | 1987-09-09 | $7700.00 | Window Closed / Lapsed |