US1706164A - Regulating system - Google Patents

Description

March 19, 1929. HULL 1,706,164

REGULATING SYSTEM Fil ed Nov. 6, 1925 Inventor: JOhT'W I. H ULL,

His Attorneg.

Patented Mar. 19, 1929.

UNITED STATES PAT JOHN L HULL, 0F SCHENECTADY NEW IQ'ORK, ASSIGNOR 1,706,164 ENT OFFICE.

COMPANY, A CORPORATION OF NEW YORK.

REGULATING SY STEM.

Application filed November 6, 1925. Serial- No. 67,472.

chine are driven by electric motors it is essential that the speed of a motor driven roll be varied in accordance with the cloth passing over' such roll, or if the cloth is being rolled up thereby, it is essential that the speed be such as to roll the cloth up at the rate of feed.:' In any such installation it is very desirable that the speed control system shall be as free from hunting as 7 possible since hunting introduces losses and non-uniformity in the product, and it is the primary object of my invention to provide aregulating system which shall be substantially free from hunting.

The features of my invention which are I believed to be novel and patentable will be I pointed out in the appended claims. Fora better understanding of my invention, reference is made in the following description to the'accompanying drawings in which F1g-. 1

is a diagrammatic representation of my invention as applied to the control of amotor driven part of a textile mill; Figs. 2 and 3 show. different positions of the switch mechanism; and Fig. 4 represents the preferred form of the -anti-hunting switch which is diagrammatically represented in Fig. 1.

In Fig.1 .there is represented apparatus for rolling up a sheet of fabric 10 as it is manufactured. I The motor llvfor driving the winding-up roll 12 ishere represented as an alternating-current commutator motor of a variable speed type, the speed .being varied by shifting the brushes on the commutator. Such a motor is described in Reissue Patent No. 14,031 to Schrage. A reversible pilot motor represented at 13 is provided for shifting'the brush yokes 15' of the motor 11 through suitable gearing represented at 14. The pilotmotor is provided with two field windings 16 and 17 and it will be understood th at when' the motor 13 is energized through one field winding 17, it will operate to shift the brushes of the motor 11 in such a direction as to lower its speed and when the motor 13 is energized through the other field winding 16, it will shift the brushes of motor 11 in the opposite direction to raise its speed. The control of the pilot motor 13 is by meansjof the switch mechanism repre .upon which rests a hollow rack 27,

sented at 18 in accordance with the rate of feed of'the fabrid 10. The fabric 10 passes through what is known in the textile industry as a compensating gate, comprising a compensating roll 20 which is free to move up and down in a guiding frame 19. The weight of the roll 20 may be partially balanced by acounterweight 21, such that the 'roll 2O keeps the fabric tight without undue strain, and raises and lowers asthe feed varies with respect to the rate at which the fabric 1s rolled up at 12. The weight 21 1s secured to a chain 22, which passes over a sprocket 23 on a shaft 24 on the top of the frame and is then secured to the slidable bearing 25 of the roll 20. The opposite side of the frame at the other end of' the roll 20 is similarly arranged. The up and down movement of the roll 20 serves to operate the switching device 18 in the manner. hereinafter described.

A preferred form of the switching device 18 isshown in Fig. 4, but for the purpose of better illustrating the principle of the invention, a more diagrammatic form of the switch is shown in Fig. 1. In Fig. 1 the switch 18 comprises a supporting base'26 geared to a pinion 28, a double ended contact rod 29 free to slide between its head pieces 30 and 30' through the hollow rack 27, contacts 31 and 31 placed in alinement with the opposite ends of the contact rod 29 and springs 32 and 32' to which contacts 31 and 4 31 are secured.

The sliding connection between rod 29 'and the hollow rack 27 develops enough TO GENERAL ELECTRIC cooperating contact.

retaining chambers 40 and 40 and the springs press the contacts against the inner ends of these chambers with more force than that required to slide rod 29 in rack 27 so that said springs are not further compressed untilthe rod 29' reaches the limit of its frictional travel through the rack 27 as determined one of the enlarged heads of said rod coming against an 'end of the rack, as shown in Fig. 2.

The pinion 28 is secured through a shaft 83 to' a chain wheel 34 andthewheel 34 is connected to another chain wheel 35 secured toshaft 24: by means of the chain 36. The chain 36 passes over an idle chain wheel or pulley 37 which is free to rotate on a cam 38 driven from any suitable part of the mill so as to give the switch rack 27 an oscillatory motion in addition to any motion imparted to it by the vertical movement of the roll 20. The chain 36 is held tight by weights 39 and 39 so as to eliminate lost motion. As the motion of thecam 38 alternatel increases and decreases the length of the c ain between chain wheels 35 and 34, the rack 27 is given the oscillatory motion above referred to and weight 39 thus also has an up and down movement in addition to any movement imparted to it by the vertical movement of roll 20.

When rack 27 moves to the right due to a lowering of roll 20, rod 29 will move with it due to friction between the rod 29 and rack 27 until .contact' is made between 30 and 31. "At this time one or more brief momentary contacts will be made because of the oscillatory motion and because as soon as contact is made, rod 29 will slide to the left with respect to the rack; The duration of contact will increase with the rate of movement of the roll 20 and thus for every revolution of cam 38 the ratio of the time that the contact is closed to the time it is contact 31 at the extreme part of. the .oscillatory movement. The pilot motor 16 will give a final fine adjustment of the brushes such as to cause roll 20 to cease its motion altogether, or perhaps to rise very slowly,

and rack 27 to creep slowly to the left until such time as the reverse operation takes place at contacts 30 and 31'. Let us suppose how- .ever that due to a larger discrepancy in speed the roll 20 descends still further than that assumed above; rod 29 will be moved through rack 27 until contact head piece 30 abuts against the. end of the. rack. Now the oscillatory movement commences to compress spring 32 instead of moving, rod 29 through the rack and the duration of'contact becomes longer, increasing the speed corrective operation of the pilot motor. Finally, when the spring is sufiicie'ntly compressed, the contact 31 will follow the contact 30 back and forth and the pilot motor circuit will remain closed continuously giving the maximum corrective' operation to the pilot motor and mosses paratively rapid rate. This condition of the switch is represented in Fig. 2. The reverse operation takes place in case the maximum correction in the opposite direction is necessary.

The central position of the switch parts 18 corresponds to the central position of the roll 20. It will appear, however, that after a partial or maximum correcting operation such as has been just described, the rod 29 no longer will be in a central position with respect to the rack 27 and roll 20, but will be moved through the rack away from the contact31, as shown for example, in Fig. 3. This is an important advantage because ordinarily after a maximum corrective operation the motor 11 will be left runnin too slow or too fast; in the case described, too

fast. It will therefore be desirable to start slowing down the motor gradually even betion and that is what happens. Furthermore, the. momentary corrective contact period is now increased to that corresponding to the maximumdistance which rod 29 can move through rack 27 so that the correction necessary to slow down the motor is anticipated by the device and is gradually applied in proportion to the need. The nature of the correction applied is therefore also dependent upon the recent past performance of the device.

In certain cases the oscillatory motion furnished by the cam 38 can be omitted since it will be evident that the'essential principles involved which accomplish a correction in speed in proportion,.to'its need and anticiates the need in time to prevent anything ut a slow hunting action will still exist without the oscillatory motion. Where this jmotion is omitted the shifting of the brushes continues at full speed until the motion of the gate is actually slightly reversedand the inertia of the pilot motor thus offers an over-correction. The addition of the oscillatory motion improves the action by moving the pilot motor but slowly when roll 20 is moving slowly, and moving it rapidly with rapid'moveme'nt of roll 20 and permits the omission of the usual pilot motor brake as well as more completely eliminating the hunting. i

It has been demonstrated that the relative proportions of the various parts of the apparatus may be so chosen as to result in a practically ne ligible amount of hunting and crawling of the variable, in thisv case the vertical movement of the roll 20.

In practice the switch mechanism is built more compactly than that above described and is placed in a box to keep out-dirt and moisture. The preferred design takes the form shown in Fig. 4. s

In Fig. 4:, '34 represents the chain wheel lar 44 secured to shaft 38 and the hub by means of a compression spring 46. However, if restrained they can slip on shaft 38. Between sleeves 42 and contact piece 43 is a torsional sprlng 47 having its ends engaging pins 49 and secured in collar 42 and gether,

contact piece respectively, in such a way that these parts will ordinarily turn tobutif contact piece 43 is held stationary and collar 42 is moved by reason of dog: 56 coming in contact with finger 41,

relative movement will occur between c0llar 42 and contact piece 43. Spring 47 is finder, sufiicient initial torsional strain to prevent relative motion of 42 and 43 even with 43 restrained, and with 43 sliding on friction collar 44 until positive motion is imparted'to 42 by engagement of the dog 56 and the collar 42/ Contact piece 43 carries contact fingers 51 and 51 on either side which cooperate with stationary contact fingers 52 and 52 to close a circuit between 52 and 52 and through them the circuit of the pilot motor for the desired direction of rotation. Preferably stop fingers 53 and- 53' are prfi ijided to-limit the movement without placing excessivestrain on the contact fingers 52 2111(1'252. .Although the parts of this switch mechanism are arrangeddifi'erently rthan diagrammatically represented in Figs. 1 to 3, it will be evident that it is designed to perform the same functions as previously described. In .Fig. 4 the switch mechanism is represented in a central position with the contacts open; Ifthe wheel 534 and shaft 38 are rotated in a counterclockwise direction facing the wheel 34,

parts 42 and 43'will move with them due to :2

the frictional engagement until contact fingers' 51 and 51 come against contacts 52 and 52 Upon further movement parts 42 and 43 will slip on shaft 38 until dog 56 eventually comes against finger 41., Upon Surther movement-of shaft 38 inthe'same irection, sleeve 42 willbeturned with it and place spring 47 under tension thereby maintaining" contacts 51 and 52 closedcontinuously. Now when the shaft is rotated in the 'opposite direction, contact. piece '43 will remain stationary, or substantially so,

until the spring 47 is unwound to its initial position where .pins 49 and 50 are in a radial line. .Then both sleeve 42 and contact shaft by friction until the contact finger on -the opposite side .(not shown) comes in contact with its stationary contact and the parts 42 and 43 will start to slip. This slipping will continue until the shaft stops rotating, or until the dog 56 comes against a finger on sleeve 42 (not shown) diametrically opposite finger 41. It will be noticed that contact 52 is carried on a "spring finger 54. This makes certain a circuit between 52 and 52 as with solid contacts it would be very difiicult to obtain simultaneous contact between 51 and 52 and also between 51 and 52.

While I have described certain specific embodiments and applications of my invention, I do not wish to be limited thereto, but seek .to cover in the appended claims all embodiments and applications of my invention coming fairly within the true scope thereof. lVhat I claim as new anddesire to secure byLetters Patent of the United States is 1. In a speedcontrol system, a motor, acontinuous material subject to a constant or variable rate of feed acted upon by said 1110- tor, and means for cont-rolling the speed of said motor in accordance with the rate of feed of said material comprising a gauging device moved in response to the difference between the rate of feed of said material and the rate it is acted upon by said motor, speed regulating means for said motor controlled by the movement of said gauging device, and means for imposing a continuous oscillatory movement on the controlling action of said gauging device. I

2. Means for regulating the speed of a motordriven textile roll in accordance with the rate of feed of the textile material comprising a gauging device movable in oppos te directions in accordance with increasing and decreasing slack 1n the material operated upon by the roll, an'electric motor for driving said roll, a speed controller for said metor, and means operating upon said speed controller in response to the position and rate of-movement of said gauging device for progressively correcting the speed of said motor in proportion to variations from a predetermined amount of slack in said material and in proportion to the rate of change in such slack.

z 3. In a motor' drive installation where a motor operates upon a continuous material which is subject to a variable rate of feed,

means for controlling the speed of said motor comprising a gauging device moved in opposite directions in response to slow .and fast rates of feed-of said material as compared-to the rate at which said motor operates thereon, a switching device having av central non-regulating range of movementm'ovable in opposite directions beyond saidnon-regulating range for respectively increasing and decreasing thespeed of said motor, a driving connection between said gauging and switching devices having a central range of movement where the drive 5 is through frictional slipping parts and having extreme r'angesof movement where the drive is through resilient positive driving connections.

4. In a motor drive installation where a 11) motor operates upon a continuous material which is subject to a variablerate of feed, means for controlling the speed of said motor comprising a gauging device moved in opposite directions in response to slow 15 and fast rates of feed of said material as compared to the rate which it is acted upon by said motor, a regulating device for said motor having a central non-regulating range of movement movable in opposite directions beyond saidnon-regulating range for respectively increasing and decreasing the speed of said motor, a driving connection between said gauging and regulating devices having a central range of movement where the drive is through frictional slipping parts and hav-- ing extreme ranges of movement where the drive is through resilient positive driving connections, and means for imposing a continuous oscillatory movementjupon the regulat-ing action of said gauging device.

5. In a speed control system wherein a motor operates upon a continuous material which is subject to a variable rate of feed, a gauging device movable in opposite directions in response to slow and fast feeds of said material as compared to the rate at -which said motor operates on said material, an electric contactor arranged to be moved in opposite directions for respectively increasing and decreasing the speed of said motor, said contactor having a freely movable central non-regulating range of movement, driving means for said contactor] moved in accordance with the movement ,of

said gauging device, a combined frictional and resilient driving connection between said driving means and contactor which permits a positive frictional drive within the freelymo'vable non-regulating range of said contactor, relative slipping between said driving means and contactor when the ganging device is moving through a central range and the contactor has been moved to a regulating position and a resilient positive drive $5 for extreme movements of said gauging device.

6. A regulating device comprising a contactor movable in opposite directions to make contact with cooperating relatively stationary contacts for respectively produc ing opposite regulating effects, said contact tor having a freely movable non-regulating range between said contacts, gauging means movable in opposite directions in re- 5 sponse to opposite regulating requirements mosses for operating said contactor, means for continuously imposing a slight oscillatory movement upon the regulating movement of said gauging means, and a frictional driving connection between said gauging means and contactor which permits said contactor to be moved against either cooperating contact and then to slip with respect to the gauging device, so that the combined movement of the gauging device and continuous oscillatory movement produces a regulation proportional to the rate of movement of said gauging device. v

7. A regulating device comprising a contactor. movable in opposite directions to make contact with relatively stationary contacts to produce opposite regulating effects, said contactor having a freely movable nonregulating range, a gauging device movable in opposite directions in response to opposite regulating requirements for moving said contactor, a frictional driving connection between said gauging device and contactor which permits positive movement of said contactor by said gauging device within the freely movable non-regulating range but which permits the contactor to slip with respect to the gauging device when it comes against said relatively stationary cooperating contacts, whereby after such regulating operation the gauging device is displaced with respect to the contactor substantially in proportion to the extent of the regulation.

8. In a speed control system, a motor, a contlnuous material subject to a ,eonstant or variable rate of -feed acted upon by said motor, and means for controlling the speed of said motor in accordance with the rate of feed of said material comprising a gauging device moved in opposite directions in response to plus and minus and minusdifferences between the rate of feed of said material and the rate it is acted upon by said motor, speed regulating means for said motor controlled by said gauging device, and means associated with said gauging device whereby the speed regulating action of said device 18 suspended as soon asthe direction of motion of the device reverses while in a central portion of the travel of said device and whereby the speed regulating action of said device remains continuous without regard to a reversal in its direction of movement in zones of travel of the device outside the aforesaid central portion.

9. In a speed control system, a motor, a continuous material subject to a constant or variable rate of feed acted upon by said motor, and means for controlling the speed of said motor inaccordance with the rate of feed of said material comprising a gauging device moved in response to a difference between the rate ofvfeed of said material and the rate it is acted upon by said motor, speed regulating means for said motor controlled by said gauging device, and means associated with sa1d gauging device for making the 10. In a speed control system, a motor, a

continuous material subject to a constant or variable rate of feed acted upon by said motor, and'means for controlling the speed of said motor in accordance with the rate of feed of said material comprising'a gauging device moved in opposite directions in response to his and minus differences between the rateoi feed of said material and the rate it is acted upon by said motor, speed regulating means for said motor controlled by said gauging device, and means associated with said gauging device for making the speed controllin actionthereof dependent upon the rate 0? motion of said device, reducing it to zero when the motion of the gauging device stops while it is in a central portion of its range of travel, but permitting a maximum speed .re ating action of said device without regar to its rate of motion when it is in zones of travel outside the aforesaid central portion.

In witness whereof, I have hereunto set my hand this 5th day of November, 1925.

J OHN I. HULL.

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