US3822045A

US3822045A - Archimedes spiral wobble control

Info

Publication number: US3822045A
Application number: US00268086A
Authority: US
Inventors: T Johnson
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1972-06-30
Filing date: 1972-06-30
Publication date: 1974-07-02
Anticipated expiration: 1991-07-02
Also published as: GB1430845A; DE2332904A1; BR7304739D0; JPS548184B2; JPS4963895A; DE2332904C2

Abstract

A control system for a pouring reel to allow a product to be deposited in the reel in continuous layers, each layer forming an Archimedes spiral. The control system produces a reel speed reference signal by dividing a signal proportional to the linear speed of the product by a signal proportional to the desired coil convolute radius of the product in the reel to obtain the desired result.

Description

United States Patent [191 Johnson [11] 3,822,045 [4 1 July2, 1974 ARCHIMEDES SPIRAL WOBBLE CONTROL [75] Inventor: Thomas D. Johnson, Roanoke, Va.

[73] Assignee: General Electric Company, Salem,

221 Filed: June 30, 1972 211 App]. No: 268,086

[52] US. Cl. 242/83 [51] Int. Cl. B2lc 47/28, 1365b 75/02 [58] Field of Search 242/83, 82; 28/21; 19/159;

[56] References Cited UNITED STATES PATENTS 3,270,978 9/1966 Whitacre 242/82 3,337,154 8/1967 Smith at 211.. 242/83 5/1969 Cole et all 242/83 5/1972 Fullers et a1. 242/82 X Primary Examiner-John W. Huc'kert Assistant Examiner-John M. Jillions Attorney, Agent, or Firm-Amold E. Renner; Harold H. Green, Jr.

[5 7] ABSTRACT result.

7 Claims, 9 Drawing Figures PMENTKEWIJIL SHEET 6? 6 IST LAYER 3RD LAYER PRODUCT SPEED I00 230 U W REEL SPEED REFERENCE 3 4OO RADIUS DETECTOR GENERATOR RATE LIFIIT REFERENCE TORQUE PROGRAM 00 800 600 7 2 v I A SPEED TORQUE k REEL Q REGULATOR REGULATOR looo REEL

PATENVEML 2 mm SHEET 3 BF 6 mON ARCI-IIMEDES SPIRAL, WOBBLE CONTROL BACKGROUND OF THE INVENTION This invention relates to a control system for a pouring reel which accepts amoving product such as that utilized in rod, bar and merchant mills and the invention is also applicable to laying heads or laying cones for wire and rod mills.

In the manufacturing of rods, bars and the like for the purpose of storage and shipment, individual billets are rolled into one continuous strand which is accumulated as a coil or coils in a tub or reel.

It is well known in the art that denser depositing or pouring of the product in the tub or reel can be accomplished by having the product deposited in the reel in a continuous Archimedes spiral with the spiral direction reversed on alternate layers.

The mechanical forces causing the product to bend in the reel to an optimum radius at any'instant are rela tively small; therefore, relatively small disturbing forces will cause undesirable radii to be formed.

Prior art attempts to achieve the formation of a coil approximating an Archimedes spiral with the spiral direction reversed on alternate layers usually utilized a control system which caused the reel to wobble or vary 7 in a manner to effect a desired pouring pattern. However, the reel was caused to wobble as a function of the reel speed. New disturbances were introduced into the control system through the use of reel gears and tachometer eccentricities. I

A further problem involved in the prior art generally caused by the torque rate capacity of a driving motor being finite was realized when each layer forming the coil in the reel required a sprial direction reversal.

The foregoing problems have been substantiallyeliminated by providing in a preferred embodiment of my invention a control system which produces a reel speed reference signal to control the angular motion of the reel. The reel speed reference signal, in accordance with this invention, is produced by dividing a signal proportional to the linear speed of the moving product by a signal proportional to the desired instantaneous coil convolute radius of the product in the reel. The above problems have further been minimized by incorporating in my preferred embodiment subsystems for continuously calculating the desired coil convolute radius of the product and for continuously calculating the desired reel torque by taking into consideration the changing inertia of the reel as the size of the coil in the reel increases.

SUMMARY OF THE INVENTION It is an object of this invention to provide a new and improved control system which will result in the denser pouring of a product into a reel.

It is another object of this invention to provide a new and improved control system for a pouring reel which will provide a fast transient response by programming the desired reel torque into the control system.

It isanother object of this invention to provide a new and improved control system which will provide a smoother and more accurate Archimedes spiral pattern of a'product to be deposited in a reel and to minimize disturbances and produce more evenly spaced convolutes of such spiral.

, his a still furtherobject to provide a new and imreel in which a reel speed reference signal controls the reel angular motion. The reel speed reference signal is derived from the division of a signal proportional to the linear speed of the product by a signal proportional to the desired coil convolute radius of the product being deposited in the reel.

BRIEF DESCRIPTION OF THE DRAWINGS The invention, both as to its organization and principle of operation together with further objects and advantages thereof may better be understood by reference to the following detailed description of an embodiment of the invention when taken in conjunction with the accompanying drawings in which:

FIG. 1 is a top view of a product being poured into a reel to'form an Archimedes spiral in accordance with this invention.

FIG. 2 is a side view of a product being poured into a reel with a cross section of the reel and associated driving mechanisms in accordance with this invention.

FIG. 3 is a graphical representation of the product deposited in a reel to forma continuous coil in three distinct layers, each layer approximating an Archimedes spiral with the spiral direction reversed in accordance with this invention.

FIG. 4 is a simplified block diagram of acontrol system for areel in accordance with this invention.

FIGS. 5a through 5d taken together as shown in FIG. 5e constitute a simplified diagram of a control system a of FIG. 4 but in greater detail in accordance with this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT For simplification, the preferred embodiment of my invention will be in the environment of a pouring reel receiving a moving product, such as a bar, in a continuous multi-layer Archimedes sprial.

Referring to FIG. 1, a bar or product 11 is delivered from a finishing stand 12 through a guide 13 into tub or reel 14 in the direction indicated by arrow 15 and rotates with the reel 14 in a direction, as indicated by arrow 16. As is well known in the: art, pins 17 are affixed inside reel 14 to provide an inner or minimum radius for the formation of an Archimedes spiral in reel 14.

In FIG. 2, product 11 is shown traveling in the direction of arrow 15 from finishing stand 12 through guide 13 into reel 14 to form the Archimedes spiral. The reel 14 comprises acoil plate 18, side wall 19 defining a maximum or outer radius, base plate 20, and pins 17 mounted on a vertical shaft 21 which rides in a fixed bearing 22. The reel 14 is driven in the direction indicated by arrows 16 in FIG. 1 about a vertical axis by driving means shown as DC motor 24, through pinion 25 and gear 26. a

FIG. 3 illustrates the product 11 in the denser coil pattern, that is, the deposition of the product in the reel in layers forming Archimedes sprials, with the spiral direction of alternate layers reversed. The pattern in FIG. 3 has three layers formed from a continuous product 11, and each layer is shown to be serially connected for clarity of illustration. The Archimedes spiral pattern is mathematically expressed as follows:

First layer, r r a 6 From r, to n.

Second layer, r r, a 0 From r, to r,,.

Third Layer, r r, a 0 From r to r,.

where:

r radius of product convolute, in feet.

a Archimedes spiral constant, in feet per radian.

0 angular displacement since initiation of the layer,

in radians.

r inner or minimum radius, in feet.

r,,= outer or maximum radius, in feet.

FIG. 4 in block diagram illustrates a transducer 100, which is positioned proximate to the finishing stand 12 (shown in FIG. I), which produces a first signal or voltage, proportional to the linear speed represented as ds/dt of a product leaving the finishing stand.

In order to develop a reel speed reference signal,

which will be used as a first input to a radius generator 300, rate limit reference 900, torque program 500 and speed regulator 600, reel speed reference means 200 is provided. Reel speed reference means 200 receives the first signal at a first input and a second signal proportional to the desired coil convolute radius r at its second input. The reel speed reference means 200 produces the reel speed reference signal at its output by dividing the first signal by the second signal thereby producing the reel speed reference signal represented as d0/dt which is equal to l/r)(ds/dt). The above equation, equal to the reel speed reference signal, is derived by the differentiation of the basic Archimedes spiral equation, r= a 0, taken for an arc segment in a manner well known in the art. 7 A radius generator 300 is provided in order to produce at its output the second signal proportional to the desired coil convolute radius which, as previously mentioned, is connected to the second input of the reel speed reference means 200. Theoutput of the radius generator is further connected to a detector 400 which detects the inner and outer radii limits and reverses the direction of radius change each time the inner and outer radii limits respectively are reached.

A torque program 500 is provided which produces a torque signal T to a first input of a torque regulator 700 which in turn regulates the torque on reel 800. The signal T which is proportional to the reel torque required to overcome inertia, is produced by multiplying a signal J, proportional to the inertia of the reel by the derivative of the reel speed reference signal, or T J (JO/dl). The torque program 500 is connected at a second input from a sensing device 1000, which provides a reel speed signal proportional to the actual reel speed. 1-,-

In order to provide an error signal to the second input of the torque regulator 700, which will modify the torque as required to maintain accurate speed, a speed regulator 600 is provided. The speed regulator 600 determines the error signal by comparing the reel speed reference signal at its first input'with the reel speed signal from sensing device 1000 at its second input.

The rate limit reference 900 which limits the second derivative of the desired coil convolute radius with respect to time to produce smooth and optimum response for reversal of the spiral constant is connected as a second input to radius generator 300 and is further connected as a third input to torque regulator 700 to limit the torque rate.

Therefore, torque regulator 700 regulates the torque on reel 800 in accordance with torque program 500, speed regulator 600 and rate limit reference 900.

Refer now to FIGS. 5a through 5d, in which, for convenience, the blocks of FIG. 4 are understood to be represented by dashed blocks. In FIG. 5a transducer includes a tachometer 101 which is utilized to produce the first signal representative of the linear speed of the product. The output of tachometer 101 is serially connected to an input of amplifier 104 through inductor 102 and resistor 106. At a point between inductor 102 and resistor 106, a bypass capacitor 103 is connected to ground. Amplifier 104 has a parallel combination of resistor 105 and capacitor 107 connected between the input and output thereof. The output of amplifier 104 is connected to ground through a combination series rheostat resistor 108, the tap of the rheostat resistor 108 is serially connected to a point A through a normally open contact 109 and resistor 112. Point A is also connected to ground through the parallel combination of reverse diodes 115, and to an output of amplifier 110 through resistor 111. Point A is further connected to an input of amplifier 110 through a resistor 114. A capacitor 113 is connected between the input and output of amplifier 110. At the output of amplifier 110 is thefirst signal proportional to the linear speed of the product.

The output of amplifier 110 is connected as the first input to the reel speed reference means 200. The output of amplifier 110 is connected to a point B at the input of amplifier 201 with filter capacitor 204 connected between the input and output thereof, through input resistor 202. Point B is further connected as an input to amplifier 201 from an analog multiplier 205 through feedback resistor 203 to provide the second signal proportional to the desired coil convolute radius. The output of amplifier 201 is connected to a first input of analog multiplier 205, a first end of resistor 304 normally open contact 302, (FIG. 5b), resistor 902, capacitor 502, resistor 517, and resistor 603 (FIG. 50). A second input of analog multiplier 205 is connected to the output of amplifier 319. Amplifier 201 and multiplier 205 divide the first signal by the second signal and result in the reel speed reference signal.

In radius generator 300 (FIG. 5b) which receives the reel speed reference signal at the first end of resistor 304, a second end of resistor 304 is connected to an input of amplifier 303. A resistor 305 is connected between the input and output thereof. The output of amplifier 303 is connected through a normally open contact 306 to a grounded rheostat 301. This output is also connected to a second end of normally open contact 302. Rheostat 301 sets the Archimedes spiral constant on the desired coil convolute spacing to be utilized in determining the desired coil convolute radius rate. Rheostat 301 is further connected to resistor 308 which in turn is connected through resistor 311 to the input of amplifier 307. Amplifier 307 has a capacitor 310 connected thereacross. Resistor 308 is further connected to the anode of diode 312 and the cathode of diode 313 and through resistor 309 to the output of amplifier 307.

The output of amplifier 307 is seriallyconnected to the input of amplifier3l5 through'resistor 317 with the parallel combination of normally closed contact 314 and capacitor 316 between the input and output thereof. The output of amplifier 315 is serially connected to relay 404 through resistor 401, diode 402, and amplifier 403, the latter four elements forming a part of the detector 400. The output of amplifier 315 is further connected through resistor 321 to the input of amplifier 319 with resistor 320 connected between the input and output thereof. The top of combination rheostat resistor 318 is connected to the input of amplifier 319 through resistor 322. The rheostat section of rheostat resistor 318 is connected to a negative DC voltage, and the resistor section is connected to ground. Rheostat resistor 318 is utilized to set the initial or maximum radius, and amplifier 319 sums this initial radius with the-radius change signal from amplifier 315 to provide the second signal r for amplifier 201.

The output of amplifier 319 is further connected to a point C through resistor 405 of the detector 400.

Point C is serially connected to a series combination rheostat resistor 410m detector 400 (which monitors the radius signal) through a bias resistor 409 and to relay 408 through diode 406 and amplifier 407. The rheostat section of rheostat resistor 410 is connected to a negative DC voltage while the resistor section is connected to ground.

The rate limit reference 900 (FIG. So) which limits the rate of change of the radius rate receives the reel speed reference signal at a first end of resistor 902 and has the second end of resistor 902 connected at point D to a negative DC voltage through resistor 901 and to a positive DC voltage through the series connection of resistor 904 and resistor 910. Point D is further connected to the input of amplifier 903; the output of amplifier 903 is connected to a point between

resistor

904 and 910 through

diodes

908 and 909. The output of amplifier 903 is further connected to the cathode of diode 312 (FIG. 5b) and then connected to point E through diode 726 (FIG. 5d) and is still further connected through resistor 906 to the input of amplifier 905 having a resistor 907 connected between the input and output thereof, and then serially connected to the anode of diode 313 and through diode 727 to point E.

The second end of capacitor 502 in torque program 500 is connected to a first input of analog multiplier 521 through the series circuit of resistor 504 connected to the input of amplifier 501, amplifier 501 having resistor 503 connected between its input and output. The output of analog multiplier 521 is applied at point F through resistor 702.

The second end of resistor 517 is connected to the input of amplifier 515 with the parallel combination of resistor 516 and diode 519 connected between the output and input thereof. The output of amplifier515 is serially connected through normally open contact 505 and resistor 520 to the input of amplifier 506. Amplifier 506 has the parallel combination of a capacitor 507 and a normally closed switch 522 with a series connected resistor 508 connected between the input and output thereof. Diode 511 is connected to the input of amplifier 506 and is also connected to a negative DC voltage through resistor 510 and to the output of amplifier 506 through resistor 509. The output of amplifier 506 is applied as a second input to analog multiplier A reel tachometer 512, which produces a reel speed signal, has its output serially connected through inductor 513 and resistor 604 of speed regulator 600 to an input of amplifier 601 with resistor 602 connected between the input and output thereof. Capacitor 514 is connected to ground at a point between inductor 513 and resistor 604. Also a point between inductor 513 and resistor 604 is connected to the input of amplifier 515 through resistor 518. The input of amplifier 601 is also connected to the second end of resistor 603. The output of amplifier 601 is connected through series resistor 703 to point F.

Point F in torque regulation 700 (FIG. Ed) is further connected to the input of amplifier 701. It is also connected to ground through resistor 704, capacitor 709, and resistor 710. The output of amplifier 701 is connected through resistor 705 to the connection between resistor 704 and capacitor 709. The output of amplifier 701 is also connected through resistor 707 to the input of amplifier 706 with resistor 708 connected between the output and input thereof. The: output of amplifier 706 is connected through resistor 711 to point E.

Point E is connected through resistor 713 to a current feedback signal terminal 712 to DC motor static armature supply 723 and is further serially connected to a firing angle reference signal terminal 730 of DC armature supply 723 through resistor 715 and amplifier 718. The current feedback signal terminal 712 is further connected to the input of amplifier 718 through the serially connected capacitor 716 and resistor 717. Connected between the input and output of amplifier 718 is the series circuit of resistor 722, capaictor 720 and capacitor 719. The point between capacitor 720 and capacitor 719 is connected to ground through a resistor 721.

Reel motor 724 with its associated shunt field exciter 731 is connected across DC armature supply 723 with normally open contactor 725 connected in series at one end of reel motor 724.

l in operation, tachometer 101 is geared to a motor which drives the finishing stand to produce a signal which is filtered by inductor 102 and capaictor 103 and amplified by amplifier 104 with further filtering by capacitor 107. The bridge 108 is adjusted in proportion to the roll diameter of the finishing stand to produce a signal proportional to the linear speed of the product 11. When contact 109 is closed, the signal is amplified by amplifier 110 with the rate of change of amplifier 110 limited by capacitor 113, resistor 114 and diodes 115. The output of amplifier 110 is a first signal proportional to the linear speed of the product or ds/dt.

This first signal is amplified by amplifier 201 and filtered by capacitor 204. A feedback voltage from amplifier 201 is multiplied in analog multiplier 205 by a second signal proportional to the desired coil convolute radius or r, thereby making the gain of amplifier 201 inversely proportional to the desired coil convolute radius. Thus, the output of amplifier 201 is its input or first signal ds/dt divided by the desired coil convolute radius or second signal, this equals the reel speed reference signal dl9/dt. Mathematically, this is expressed as d0/dt l/r)(ds/dt).

Differentiation of the basic Archimedes spiral equation, r= a 6, produces the equation dr/dt a (dB/dz) which is the desired coil convolute radius rate. A radius rate signal dr/dt is obtained by multiplying the reel speed reference signal dO/dt by the Archimedes spiral constant a, or by the desired coil convolute spacing as set by the rheostat 301.

For decreasing radius, the reel speed reference signal is applied to rheostat 301 through contact 302. For increasing radius, the reference polarity is reversed by amplifier 303, and the reel speed reference signal is applied to rheostat 301 through contact 306. The radius signal rate dr/dt is amplified by amplifier 307 with its rate of change limited by capacitor 310, resistor 311,

diodes

312 and 313 and a voltage from the rate limit reference 900. This limits the rate of change of radius rate or the second derivative of radius d rldt The purpose of this limit, which is controlled by the reel speed reference signal, is to produce smooth reversal of the spiral constant at the maximum rate permitted by the machine torque rate capacity. In a practical arrangement, the machine torque rate capacity exceeds the torque rate required for generating a spiral layer, therefore, the limit on a' r/dt does not have an effect except during reversal of the spiral constant.

When the reel speed is being wobbled or varied, contact 314 is open. A radius change signal dr is produced by integrating the radius rate signal dr/dt with respect to time by amplifier 315.

The initial radius is preset by rheostat resistor 318 and the total radius signal or second signal r proportional to the desired coil convolute radius is produced by summing in amplifier 319 the initial preset radius with the radius change signal. This second signal then is applied to the analog multiplier 205 to produce the reel speed reference signal as previously described.

In detector 400, the radius change signal dr is monitored by resistor 401, diode 402, amplifier 403, and relay 404 so that the outer radius r, is sensed, and relay 404 is energized when the radius is equal to or greater than the initial radius or value set by rheostat resistor 318. The second signal r" is monitored by resistor 405, diode 406, amplifier 407, and relay 408 with a bias for resistor 409 in rheostat resistor 410 so that the inner radius is sensed, and relay 408 is energized when the radius is equal to or less than the value set by rheostat resistor 410.

Referring to torque program 500, which basically produces a signal proportional to desired reel torque by multiplying a signal, either fixed or variable, proportional to the reel inertia by the second derivative of the desired angular displacement of the reel with respect to time. The derivative of the reel speed reference signal or 11 6/11? is provided by differentiating the reel speed reference signal with respect to time by amplifier 501 with capacitor 502 and

resistor

503 and 504. When the product is not being delivered to the reel, contact 522 is closed, and contact 505 is opened; and amplifier 506 will produce a signal proportional to the empty reel inertia as determined by capacitor 507,

resistors

508, 509, 510 and diode 511. When the product is sensed, contact 522 opens and the reel inertia signal is stored by capacitor 507.

The reel speed signal from tachometer 512 is filtered by inductor 13 and capacitor 514 and summed with the reel speed reference signal by amplifier 515 with

resistors

516, 517, and 518 so that amplifier 5.15 produces a voltage proportional to the speed error except that the output will only be produced if the'speed is lower than the reference because of diode 519. When varying the reel speed, contact 505 will close a time delay after each time contact 302 is closed, and it will remain closed until contact 302 is open. v

As coil size increases, the reel inertia increases, thus tending to cause the reel speed signal to be lower than the reel speed reference signal while the reel is accelerating until the inertia signal J is increased in proportion to the increase in inertia. This occurs when contact 505 is closed, and amplifier 515 transmits a current to amplifier 506 through resistor 520 thus causing inertia signal J to increase. Analog multiplier 521 multiplies the derivative of the reel speed reference signal or a' l/dt by inertia signal J to produce the torque program T== J (d i9/dt The filtered output of the reel tachometer 512 is summed with the reel speed reference signal by amplifier 601 to produce a speed error signal. This speed error signal modifies the torque program to reduce low frequency and steady state errors resulting from friction and changes in circuit parameters. This results in the necessary speed accuracy with a slow enough response to produce the necessary insensitivity to undesirable disturbances from the tachometer and to permit proper operation of the inertia compensation amplifier 506 as previously described.

The torque program signal is summed with the speed error signal by amplifier 701 and is further amplified by amplifier 706. Capacitor 709 provides a faster response, and resistor 710 provides reduced sensitivity to noise at high frequencies.

Since the reel is driven by a DC motor with a fixed shunt field and in such a machine the torque is proportional to the armature current, then the output of amplifier 706 constitutes a motor current reference signal. The motor current reference signal is applied through resistor 711 and is summed with a current feedback signal from terminal 712 through resistor 713 to produce a current rate reference signal at point E. The current rate reference signal applied through resistor 715 is summed with the current rate feedback signal at the input to amplifier 718. Amplifier 718 provides a firing angle reference signal at terminal 730 for the static armature supply 723 which in turn provides the armature voltage for reel motor 724 when contactor 725 is closed. The current rate for reel motor 724 is limited by limiting the current rate reference signal with

diodes

726 and 727 and by limiting the voltage from the rate limit reference 900. As a result, the current rate and current are regulated in response to the motor current reference signal in a manner well established in the art.

Since a DC motor is capable of commutating higher current rate when running at lower speeds, the voltage produced by the rate limit reference 900 is reduced at higher speeds in a manner well known in the art. A fixed bias to resistor 901 is summed with the reel speed reference signal by amplifier 903. Amplifier 903 provides rate limit reference voltage for one polarity through

diodes

312 and 726; and a rate limit reference voltage of opposite polarity is provided through

diodes

313 and 727 by amplifier 905 to invert the polarity of amplifier 903.

in practice, while a coil is being removed from a reel, the reel is stopped and

contacts

109, 302, 306, 505 and 725 are open and contacts 314 522 are closed. When the coil removal is completed,

contacts

109 and 725 close thus causing the reel to accelerate at. a rate deter- 9 r v mined by amplifier 110 to a speed synchronized with the product at a radius determined by rheostat resistor 318. A sensor (not shown) senses when the product arrives at the reel. When the product is sensed,

contacts

314 and 522 open, and after a predetermined time delay contact 302 closes. This time delay is to permit enough product to accumulate in the reel before wobbling starts so there will not be slippage between the coil and the reel. When contact 302 closes, the radius decreases, as previously described, and the reel accelerates.

Contact 505 closes a time delay after contact 302 closes to permit coil inertia compensation. When relay 408 detects the inner radius, as determined by rheostat resistor 410, contacts 302 and 505 open and contact 306 closes causing the spiral constant to reverse at a rate determined by amplifier 307. The radius increases as previously described, and the reel decelerates. When relay 404 detects the outer radius, contact 306 opens and contact 302 closes again. This cycle repeats continuously until the coil is completed. When the product sensor senses completion of the coil, the wobbling is interrupted, contacts 109 302, and 505 open, and contact 306 closes, the reel decelerates at a rate determined by amplifier 110 and the radius increases. When relay 404 senses that the second r signal has returned to the preset value, contact 306 opens, and the second r" signal is held at its preset value and the reel continues to decelerate until it stops. A voltage relay (not shown) senses when the reel is stopped and causes contactor 725 to open and

contacts

314 and 522 to close. Thus, the reel is returned to the original condition to permit coil removal, and the entire process repeats.

it has been shown that by providing a reel speed reference signal to control a pouring reel, that a denser pouring will result.

While an embodiment and application of this invention has been shown and described, it will be apparent to those skilled in the art that many more modifications are possible without departing from the invention concept herein described. The invention, therefore, is not to be restricted except as is necessary by the prior art and by the spirit of the appended claims.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. In apparatus for pouring a moving product into a reel, a control system for controlling the reel angular motion to allow the deposition of the product in the reel in continuous layers, each layer forming a coil approximating an Archimedes spiral, with the spiral di- 10 rection reversed on alternate layers, the control system comprising: y

a. means for continuously producing a first signal proportional to the linear speed of the product;

b. means, including'means for establishing a spiral constant, for continuously producing a second signal proportional to the desired coil convolute radius as a function of a reel speed reference signal and said spiral constant;

c. reel speed reference means'for dividing said first signal by said second signal thereby producing said reel speed reference signal at the output of said reel speed reference means; and,

d. means controlling the reel angular motion in response to said reel speed reference signal.

2. A control system as in claim 1 wherein said means for producing a second signal includes means for continuously calculating the desired coil convolute radius of the product. i

3. A control system as in claim 2 further including limiting means for limiting the second derivative with respect to time of said second signal.

4. A control system as in claim 3 further including means for determining maximum and minimum allowable values for the second derivative of said second signal as a function of said reel speed reference signal.

5. A control system as in claim 1 wherein the means for controlling the reel angular motion includes means for continuously calculating the desired reel torque, comprising;

a. means for producing an inertia signal proportional to the inertia of the reel;

b. means responsive to said inertia signal and said reel speed reference signal for producing a third signal proportional to the desired reel torque; and,

c. means for continuously regulating the reel torque in-response to said third signal.

6. A control system as in claim 5 wherein said means for continuously calculating the desired reel torque includes means for differentiating said reel speed reference signal thereby producing a fourth signal, and means for multiplying said fourth signal by said inertia signal thereby producing said third] signal proportional to the desired reel torque.

7. A control system as in claim 6 including means for increasing said inertia signal in proportion to the inertia increase of the reel as the size of the coil in the reel increases.

Claims

1. In apparatus for pouring a moving product into a reel, a control system for controlling the reel angular motion to allow the deposition of the product in the reel in continuous layers, each layer forming a coil approximating an Archimedes spiral, with the spiral direction reversed on alternate layers, the control system comprising: a. means for continuously producing a first signal proportional to the linear speed of the product; b. means, including means for establishing a spiral constant, for continuously producing a second signal proportional to the desired coil convolute radius as a function of a reel speed reference signal and said spiral constant; c. reel speed reference means for dividing said first signal by said second signal thereby producing said reel speed reference signal at the output of said reel speed reference means; and, d. means controlling the reel angular motion in response to said reel speed reference signal.

2. A control system as in claim 1 wherein said means for producing a second signal includes means for continuously calculating the desired coil convolute radius of the product.

5. A control system as in claim 1 wherein the means for controlling the reel angular motion includes means for continuously calculating the desired reel torque, comprising; a. means for producing an inertia signal proportional to the inertia of the reel; b. means responsive to said inertia signal and said reel speed reference signal for producing a third signal proportional to the desired reel torque; and, c. means for continuously regulating the reel torque in response to said third signal.

6. A control system as in claim 5 wherein said means for continuously calculating the desired reel torque includes means for differentiating said reel speed reference signal thereby producing a fourth signal, and means for multiplying said fourth signal by said inertia signal thereby producing said third signal proportional to the desired reel torque.