US2980967A - Detecting and control arrangment - Google Patents

Description

Aprll 25, 1961 R. E. MUNFORD ETAL 2,980,967

DETECTING AND CONTROL ARRANGEMENT Filed May '29, 1959 3 3 TO EMF I SOURCE IIOV AC TO EMF SOURCE a. 3 o' Q S g INVENTORS I ROBERT E. MUNFORD V PHILIP N. SMITH BY CHARLES GRAHAM S6 TORNEY 6 United States Patent DETECTING AND CONTROL ARRANGEMENT Robert E. Munford and Philip N. Smith, Clemspn, S.C;, and Charles E. Graham, Greensboro, N .'C., asslgnors to Deering Milliken Research Corporation, Pendleton, S.-C., a corporation of Delaware Filed May 29, 1959, Ser. No. 816,940

25 Claims. (Cl. 19-70) This invention relates to a repetitive phenomenon analyzer, and more particularly to an arrangement for detecting the occurrence of a selected particular periodically repetitive fault, specifically such a fault as occurs in sliver processing apparatus such as pin drafting machines.

In the processing of sliver as formed by pin drafting apparatus, a fairly common and serious problem is the periodic very large abrupt change in sliver diameter as a result of malfunctioning of a certain part or parts, e.g. the faller bar, of the pin drafting apparatus. This defeet is quite serious since once it begins it occurs con-' tinuously at a definite periodic linear time interval along the sliver, and the continuing recurrence of such defect shows up in the finished cloth as a definitely visible pattern, causing this cloth to be graded as second, with material monetary loss resulting therefrom. It is an object and feature of this invention to detect such periodic time-interval spaced defects, particularly those periodic defects of the type resulting from defective faller bar operation in a pin drafter, and to stop the pin drafting or other processing apparatus before a large amount of sliver yardage has been formed with this defect therein.

Still other objects, features and advantages of the invention will become apparent to those skilled in the art from a reading of the following detailed description of a preferred embodiment according to the invention, taken in conjunction with the accompanying drawing wherein The figure is a schematic circuit diagram of a preferred embodiment.

Referring to the drawing, a detector 11 which is sensitive to the variations in thickness of the sliver is suitably disposed at the output end of a pin drafter apparatus generally indicated at 12. The detector 11 may suitably take the form of a movable sliver engaging finger connected in controlling relation to a mechanically movable potentiometer, a photocell arrangement, or other suitable desired transducer arrangement yielding a signal which is a function of the sliver diameter. The particular detector arrangement employed is not per se a novel aspect of the invention, and inasmuch as any of variousdilferent arrangements may be employed by those skilled in the art, the detector is for the sake of simplicity merely shown in block form and will not be further described herein. This signal may be fed through one or more stages of an AC. amplifier 13 to a relay having two pairs of normally open contacts 15a, 15b. Inasmuch as there may normally be no serious reflection in the quality of the finished cloth resulting from comparatively gradual fairly large changes in sliver diameter, whereas large abrupt periodically spaced changes cause serious quality defects, the illustrative apparatus is preferably arranged only to detect and operate as a result of a large relatively abrupt change of a selected periodic nature in the sliver diameter. Accordingly, while a signal is continuously generated by the detector in the preferred embodiment directly proportional to the sliver diameter, the AC. amplifier 13 is elfective to deenergize the relay 15 only upon the occurrence of a signal in the 2,980,967 Patented Apr. 25, 1961 form of an abrupt pulse or change in the signal exceeding a selected minimum amplitude, resulting from a corre sponding abrupt large change in the diameter of the sliver.

A plurality of ganged sequence and timing cams C C and C are provided, andare driven by a suitable constant speed motor M to provide for analysis of the signals from the detector 11, amplifier 13 and relay 15. Two pairs of contacts 15a and 15b of the relay 15 are normally held open by maintaining the relay 15 normally energized in the absence of a signal from detector 11 satisfying the minimum conditions of abruptness and amplitude sufficient to cause the amplifier 13 to deenergize :the relay 15. Deenergization of the relay 15 eifects the closing of a cam motor drive circuit through initially closed cam contacts 17a, 19a a constant speed cam drive motor M, and relay contacts 15a. This also effects energization of a holding relay 20, which in turn closes holding relay contacts 20a to thereby hold the cam drive motor M energized after opening of the relay contacts 1'5a at the end of the momentary pulse from the detector 11. The cam switch arm'17 associated'with the cam C is resilient and has a high strain recovery rate or bending return compliance rate (defined for the present purpose as the rate of bending movement under internal or external stress), whereas corresponding contact arm 19 associated therewith is also resilient but has a relatively low strain recovery rate or bending return compliance as compared to the bending return compliance rate of the switch arm 17. These arms 17 and 19 may be constructed of any suitable materials satisfying these bendmg compliance requirements. For instance, the arm 19 may be formed of metal and the arm 17 of polystyrene, each with a metal conductor disposed thereon for circuit continuity to the contacts thereon, or both arms 17 and 19 may be of the same material, with the arm 19 being of greater lateral thickness in the direction of bending motion than the arm 17. Each of these arms 17 and 19 1s positioned so as to be self-resiliently biased toward the cam C to the end that the contacts 17a and 19a of the two contact arms are closed both in the initial recessed position as shown in Figure l and in the outwardly biased position which occurs while the cam follower 17b on the contact arm 17 is riding on the raised portion of the cam C These contact arms 17 and 19 break contact only at the end of the cycle when the cam follower 17b abruptly moves into the recess of cam C while the relatively low compliance contact arm 19 does not follow the high compliance arm 17 as quickly,

and thus permits the contacts 17a and 19a on there- 'type is employed in association with a pair of additional cams C and C to stop the pin drafting machine upon the'occurrence of a preselected number (four, in the instant example) of recurrences of abrupt defects with a specific time interval therebetween (e.=g. the recurring defect resulting from a defective faller bar). Other defects, even through abrupt and large, will not cause stopping-of the machine by this device. -The main stepping relay coil 23 is actuated when the cam contact arm 25 and contact 27 associated with the cam C and the second relay contacts 15b associated with relay 15 are concurrently in closed position. The closing of either of these two pairs of contacts alone will not cause the energization of the stepping relay coil 23. The stepping relay switch 21 is reset by an auxiliary reset coil 29 which is actuated by the closing of the contact arm 31 and contact 33 associated with the cam C or by closing of auxiliary switch contacts 35, later described. Only upon the stepping relay contact arm 23a moving to contact 3 is the pin drafting machine stopped. Thus, it is necessary that four successive specific interval spaced defects occur in order for this device to stop the processing apparatus. Any lesser number of defect occurrences will only result in the stepping relay arm moving to interconnected positions 0, l, or 2, with reset of the stepping relay resulting from the next initiating pulse of sufiicient abruptness and strength to deenergize relay 15 as will be later described in more detail.

In the illustrative embodiment the cam C has three equally spaced apart recesses, the first recess being spaced from the initial stopped position of the cam by the same angle (e.g. 90) as the succeeding angles between each of the three adjacent recesses. If after one-fourth of a revolution of the cam C corresponding to a pre-selected time interval, there is a second pulse from the detector 11, the relay contacts 15b and the cam contacts 25, 27 will be closed at the same time to thereby close stepping relay vcoil 23 and move the stepping relay arm 2311 one position to contact 1. Thus, after the initiating pulse three succeeding pulses from the detector at times corresponding to the next three succeeding closings of the cam contacts 25, 27 will cause the stepping relay 23a to be moved to contact 3, thereby opening the energization circuit for normally energized stop relay 37, this stop relay 37 being energized when the relay arm 23a is on any of interconnected contacts 0, 1, or 2, which causes opening of the relay contacts 37a and stopping of the pin drafting apparatus 12. If desired, an indicating device such as a light 39, buzzer, or the like may be connected in series with the relay contact 3 for energization upon the occurrence of the selected number of interval repetitions of the selected phenomenon (e.g. the taller bar induced defect).

If only one, two, or no additional pulses are received from the detector during this cycle of the cams, the motor cam will proceed to turn the cam to the position shown in the drawing, whereby the cam contact arm will drop into the recess on cam C to momentarily open the motor holding circuit and stop the motor M, the holding relay 20 dropping out as a result of this momentary opening of the contacts 17a and 19a on the arm 17 and 19. It will be seen also that the cams will be progressed to this position irrespective of whether the stepping relay switch arm is progressed to its contact 3, thus placing the circuit in readiness condition for further detecting of pulses of a succeeding sequence upon restarting of the controlled apparatus (i.e. the pin drafter 12).

Upon the stopping of the machine by the opening of the stop relay, the stepping relay contact arm 23a is disposed at contact 3. In order for the operator to be able to start the machine, it is necessary for him to raise the pivoted faller bar cover, schematically indicated at 12a, which is operatively connected to and effects the closing of the alternate pair of normally open reset contacts 35, operatively connected to the taller bar cover 12a for actuation as a function of the raising of the cover. The raising of the taller bar cover 12a closes the contacts 35 to thereby close the alternate energizing circuit for reset relay coil 29. Thus energized the reset relay coil 29 resets the switch 271 and this in turn closes the energizing circuit for stop relay 37 to thereby energize the stop relay 37 and close relay contact 37a. This assures that the operator will at least look at the defective apparatus (i.e. faller bar assembly) before restarting the machine. In this instance, after the stopping of the machine by the present device, the cam Q, will have no effect during the next succeeding rotation of the cams C C since the stepping relay is already reset to the starting position 0. However, in those instances where the cams C -C have been run through a cycle without the necessary four successive interval pulse occurrences, upon the next energization of motor M by a suitable signal from detector 11 the cam C will during its first 90 of rotation close the contacts 31, 33 to energize the reset relay 29 and reset the stepping relay 4 23a to 0 prior to the first closing of the contacts 25, 27 associated with the pulse sequence analysis cam C As a saftey measure a suitable step-down transformer T may be utilized for such portions of the circuit as may require exposed wiring or other parts of the circuitry which might otherwise constitute a hazard to the machine operators or other personnel.

While the preferred embodiment has been illustrated as including normally energized relays 15 and 37, and such arrangement is most desirable for the purpose of providing a fail-safe mode of operation for the device, it will be apparent that if one desires to forego the desirable fail-safe feature these relays may be arranged to be normally deenergized. In such an alternative arrangement, for instance, the stepping relay switch 21 would not need to be of the make-before-break type and the contacts 0, 1, and 2 would not have to be tied together. The relay 37 might in such an alternative arrangement be arranged in parallel with the stop indicating light and in series with the relay contact 3, instead of the contacts 0-2. Each of the relays 15 and 37 might have their respective contacts in the same position in the deenergized condition of these relays as is illustrated in the drawing and described in the present embodiment as being applicable to the position of the contacts when the relays 15 and 37 are energized, this being their normal operating condition in the present embodiment as discussed above.

It will be appreciated that while the requirement of four consecutive defect occurrences is preferred in the present application of the invention the precise number of defect repetitions required for actuating the device may be varied as desired and as the particular situation may require or render desirable. Thus the device might be arranged to stop the machine upon the occurrence of a larger or smaller number of occurrences, if desired, although normally less than three occurrences do not give any real assurance that the particular selected defect is present, and in most instances, it is preferable to require three of four or more phenomena recurrences for final control.

While the preferred embodiment of this invention has been specifically described as applied to a monitoring device for detecting periodically repetitive faults in sliver processed by pin drafting machines, it will be apparent that the invention is not restricted to this specific application nor to the specific illustrative construction disclosed herein but that the invention may be equally ap plicable to other types of apparatus and in other forms or embodiments. Accordingly, it is to be understood that many modifications and improvements may be made without departing from the scope and spirit of the invention, the invention being therefore limited only by the scope of the appended claims.

We claim:

1. A repetitive phenomena detecting and analyzing arrangement comprising means for detecting repetitive occurrences of a selected intermittent phenomenon expected by means other than said detecting and analyzing arrangement, time interval indicating means yielding an indication of a selected time interval, means for comparing the time interval between repetitive occurrences of said phenomenon with a selected predetermined time interval indicated by said time interval indicating means, and means for initiating a control phenomenon in response only to a selected repetition at a selected time interval of said selected intermittent phenomenon.

2. A repetitive phenomena detecting and analyzing arrangement comprising means for detecting the occurrences of a selected phenomenon, time interval indicating means yielding an indication of a selected time interval, means for comparing the time interval between repetitive occurrences of said phenomenon with a selected predetermined time interval indicated by said time interval indicating means, and means for initiating a control phenomenon in response to a selected repetition of said selected phenomenon at a selected time interval, said time interval indicating means comprising a cam, means for moving said cam, and a cam follower switch operatively connected to said cam and adapted to be opened and closed in response to movement of said cam, said cam follower switch being operatively connected to said initiating means.

3. A repetitive phenomena detecting and analyzing arrangement comprising means for detecting the boomrences of a selected phenomenon, time interval indicating means yielding an indication of a selected time interval, means for comparing thetime interval between repetitive occurrences of said phenomenon with a selected predetermined time interval'indicated by said time interval indicating means, and means for initiating a control phenomenon in response to a selected repetition of said selected phenomenon at .a selected time interval, said comparing means comprising a first switch adapted to be.

actuated upon termination of each of said selected time intervals and a second switch adapted to be actuated in response to each occurrence of saidselected phenomenon, and an .electro-responsive device operatively connected to each of said switches and adapted to be actuated only in response to concurrent actuation of each of said switches.

4. Apparatus according to claim 3 wherein said switches are normally open, said switches and said electro-responsive device being in series connection.

5. Apparatus according to claim 3 wherein said electroresponsive device comprises a stepping relay.

6. Apparatus according to claim 5 further comprising means for resetting said relay in response to occurrence of said selected phenomenon prior to each initial comparison of the repetitive occurrence of said phenomenon with said selected predetermined time interval indication.

7. Apparatus according to claim 6 wherein said resetting means comprises a cam and cam follower switch, and a reset relay operatively connected in controlled relation to said cam follower switch and in reset controlling relation to said stepping relay.

8. Apparatus according to claim 7 wherein said resetting means further includes an auxiliary reset switch operatively connected in controlling relation to said reset relay.

9. Apparatus according to claim 8 further comprising a device having means capable of causing said selected phenomenon, said device having a movable part associated therewith, said movable part being operatively connected in controlling relation to said reset switch, and said detecting means being operatively connected in phenomena detecting relation to said device.

10. Apparatus according to claim 9 wherein said device comprises a textile processing machine.

11. Apparatus according to claim 10 wherein said device comprises a pin drafter machine having a faller bar arrangement with a faller bar cover, said faller bar arrangement comprising said means for causing said selected phenomenon, said faller bar cover comprising said movable part.

12. Apparatus according to claim 1 wherein said comparing means comprises a first switch adapted to be actuated upon termination of each of said selected time intervals and a second switch adapted to be actuated in response to each occurrence of said selected phenomenon, and an electro-responsive device operatively connected to each of said switches and adapted to be actuated only in response to concurrent actuation of each of said switches, said electro-responsive device comprising a counting relay, and a reset switch operatively connected in reset controlling relation to said counting relay, a device having means capable of causing said phenomenon, said device having a movable part associated therewith, said movable part being operatively connected in controlling relation to said reset switch, and said detecting means being operatively connected in phenomena detecting relation to said device.

- phenomenon, said faller bar cover comprising said movable part.

15. Apparatus according to claim 1 wherein said detecting means is responsive to variations in an extent of textile material.

. 16. Apparatus according to claim 15 wherein said detecting means is responsive to the diameter of a strand of textile sliver, and includes signal generating means adapted to generate a signal as a function of sliver diameter, an AC. amplifier operatively connected to the output, from said generating means, and a relay operatively connected to said A.C. amplifier, said relay having two pairs of normally open contacts and being responsive to a signal to close said contacts, said contacts being operatively connected in controlling relation to said comparing means and said time interval indicating means.

17. Apparatus for analyzing repetitive phenomena occurrences comprising means for, detecting the occurrences of a selected intermittent phenomenon, time interval indicating means operatively connected to said detecting means and responsive to said detecting means to yield an indication of a selected time interval after the occurrence of a first one of said selected phenomenon, means for comparing the time interval between repetitive occurrences on said phenomenon with a selected predetermined time interval indication by said time interval indicating means, and means for initiating a control phenomenon in response to a selected plurality of repetitions of said selected phenomenon at a repeated selected time interval.

18. Apparatus according to claim 17, further comprising means for placing said time interval indicating means and said comparing means in initial readiness condition upon the termination of a selected number of time intervals after one occurrence of said selected phenomenon Without the occurrence of said selected plurality of repetitions of said selected phenomenon within said last mentioned selected number of selected time intervals.

19. A repetitive phenomena detecting arrangement comprising signaling means responsive to occurrence of a particular phenomena and having a signal output, a timing device adapted to give an indication of the passage of a predetermined period of time and being operatively connected in controlled initiating relation to the output from said signaling means, and an apparatus controlling arrangement operatively connected to said timing device and the output from said signaling means, said apparatus controlling arrangement being responsive to concurrent occurrence of a selected time interval indication and a selected signal from said signaling means.

20. In combination the arrangement according to claim 19 wherein said signaling means includes a textile fault detecting transducer, said combination further comprising a textile processing apparatus, said transducer being arranged in textile fault detecting relation to said textile processing apparatus, and said apparatus controlling arrangement being operatively connected in stop-controlling relation to said textile processing apparatus.

21. Apparatus according to claim 6 wherein said resetting means comprises a reset relay operatively connected in reset controlling relation to said stepping relay.

22. Apparatus according to claim 6, further including in combination therewith a device having means capable of causing said selected phenomenon, said device having a movable part associated therewith, said movable part being operatively connected in controlling relation to said relay-resetting means, and said detecting means being operatively connected in phenomena detecting relation to said device.

23. A repetitive phenomena detecting and analyzing arrangement comprising means for detecting the occurrences of a selected phenomenon, time interval indicating means yielding an indication of a selected time interval, means for comparing the time interval between repetitive occurrences of said phenomenon with a selected predetermined time interval indicated by said time interval indicating means, and means for initiating a control phenomenon in response to a selected repetition of said selected phenomenon at a selected time interval, said comparing means comprises a first condition responsive means adapted to be actuated upon termination of each of said selected time intervals and a second condition responsive means adapted to be actuated in response to each occurrence of said selected phenomenon, and an electroresponsive device operatively connected to each of said condition responsive means and adapted'to be actuated only in response to concurrent actuation of each of said condition responsive means, said electro-responsive device comprising a counting device, and a reset switch operatively connected in reset controlling relation to said counting device, a further device having means capable of causing said phenomenon, said further device having a movable part associated therewith, said movablepart being operatively connected in controlling relation to said reset switch, and said detecting means being operatively connected in phenomena detecting relation to said further device.

24. A repetitive phenomena detecting arrangement comprising signaling means responsive to occurrence of a particular intermittent phenomenon to effect a particular output signal indicative of said phenomenon, a timing device adapted to give an indication of the passage of a predetermined period of time and being operatively connected in controlling initiating relation to a selected output signal from said signaling means indicative of the occurrence of said particular intermittent phenomenon, and an apparatus controlling arrangement operatively connected to said timing device and the output from said signaling means, said apparatus controlling arrangement being effectively responsive only to a selected number of concurrent occurrences of a selected time interval indication by said timing device and said selected output signal from said signaling means.

25. Apparatus according to claim 24 wherein said timing device is responsive only to an output from said signaling means indicative of occurrence of said particular intermittent phenomenon and exceeding a predetermined selected minimum signal value.

References Cited in the file of this patent UNITED STATES PATENTS 2,641,960 Strother June 16, 1953 2,681,475 Raper June 22, 1954 2,805,449 Martin Sept. 10, 1957 2,812,553 Coulliette Nov. 12, 1957 FOREIGN PATENTS 212,094 Australia Oct. 24, 1957

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