US3751893A

US3751893A - Strand detection

Info

Publication number: US3751893A
Application number: US00193683A
Authority: US
Inventors: W Goodhue; T Pitts
Original assignee: Leesona Corp
Current assignee: Leesona Corp
Priority date: 1971-10-29
Filing date: 1971-10-29
Publication date: 1973-08-14
Anticipated expiration: 1990-08-14

Abstract

A tender patrols the spinning stations of a spinning frame and stops to service any station requiring attention. One reason for stopping the tender is because a strand normally spun into yarn has broken at a spinning station. In order to determine whether or not the strands are advancing normally at the spinning stations, the tender carries a transducer responsive to vibration of a feeler upon engaging the normally advancing strands to actuate an electronic switch which provides a signal permitting the tender to continue its patrolling operation. If a strand is not advancing normally the signal is not provided and the tender stops to service the station.

Description

United States Patent 91 Goodhue et a1.

[ STRAND DETECTION [75 1 Inventors: William V. Goodhue, North Kingstown; Thomas E. Pitts, Cranston, both of R1.

[52] US. Cl 57/34 R, 57/54, 57/81,

242/355 R, 242/36 [51] Int. Cl D01h 13/16 [58] Field of Search 57/34 R, 52, 53,

57/54, 80, 81; ZOO/61.18; 242/35.5 R, 35.6 R,

[56] References Cited UNITED STATES PATENTS 10/1 968 B61161: a1 57/53 x 11/1968 Guido et a1. 5/1970 Bell et a1 ZOO/61.18 x

[ 1 Aug. 14, 1973 Primary Examiner-John Petrakes Assistant ExaminerCharles Gorenstein Attorney-Albert P. Davis et al.

[57] ABSTRACT A tender patrols the spinning stations of a spinning frame and stops to service any station requiring attention. One reason for stopping the tender is because a strand normally spun into yarn has broken at a spinning station. In order to determine whether or not the strands are advancing normally at the spinning stations, the tender carries a transducer responsive to vibration of a feeler upon engaging the normally advancing strands to actuate an electronic switch which provides a signal permitting the tender to continue its patrolling operation. If a strand is not advancing normally the sig- 11211 is not provided and the tender stops to service the station.

8 Claims, 3 Drawing Figures Patented Aug. 14, 1973 3,751,893

INVENTORS WILLIAM V GOODHUE By THOMAS E. PITTS ATTdRNEYs STRAND DETECTION This invention relates to strand handling apparatus and, more particularly, to such apparatus having a system for scanning strand advancing stations and determining the condition of the strands at the stations.

BACKGROUND OF THE INVENTION Strand handling apparatus including a patrolling tender for servicing spinning stations of a spinning frame is shown in a Leesona Corporation patent, U. S. Pat.

No. 3,403,866. When the tender comes upon a station requiring servicing the tender stops and doffs the bobbin at the station, dons an empty bobbin core and starts a strand winding onto the core, whereupon the tender resumes its patrolling operation. The tender carries various sensors for determining the condition of the station. One of these sensors is an ends down detector in the form of a pivoted bail for engaging the normally advancing strands. The bail is normally supported by the strands. If a strand is broken or sufficiently slack the bail drops closing a switch which normally initiates a work cycle of the tender. A hail of this type is usually relatively wide so that after dropping upon detecting the absence of a strand the bail may readily be camm ed back to its normal position by the next normally advancing strand. An ends down bail must drop readily when coming upon an end down and must be freely and easily returned to its normal position by the next normally advancing strand. Thus, the pivotal mounting of the bail must be well maintained and kept free of lint or other matter which might impare its movement, and care must be taken to avoid distorting the bail during servicing to the tender. Also, a bail sensor of this type cannot differentiate between a taut, standing strand and a normally advancing strand.

Additionally, various photo-responsive sensors are known for determining when a strand is advancing normally. Such photocell sensors may be undesirably affected by ambient light and may incorrectly respond to indicate a standing strand as a normally advancing strand. Most photocells are likely to respond inconsistently to different colors and sizes of strands which may concurrently be wound at different stations of the spinning frame. Also, the ever present lint and dust or other foreign matter may also adversely affect response ofsuch photocell sensors.

Other known ends down sensors include various piezoelectric and magnetic devices which respond to movement of an advancing strand on a 'per spindle basis. Such devices are generally in constant engagement with the strands and therefore apply a constant drag as well as wear on the strands and may cause excessive linting of the strands. Such per spindle devices in their known forms have little, if any, applicability for use on patrolling tenders.

SUMMARY OF THE INVENTION It is, therefore, a primary object of this invention to provide a new and useful strand handling apparatus for overcoming these and other shortcomings of prior ends down detecting systems.

Another object is provision of a new and useful apparatus having a plurality of strand advancing stations and a system for responding to the condition of strands at the stations.

A more specific object is provision of a new and useful apparatus having a plurality of strand advancing stations and a patrolling system for responding to the condition of the strands at the stations and including a feeler responsive to engaging the normally advancing strands one after another, and a transducer responsive to the feeler responding to the advancing strands for actuating an electronic switch for providing a regulating signal. A related object is provision of a feeler which vibrates in a particular manner to initiate the signal. Another related object is provision of a flexible feeler for camming onto engagement with and gliding across the strands.

The invention, in brief, is directed to strand handling apparatus having a system for responding to a nonnally advancing condition of strands being processed at a plurality of strand advancing stations. A feeler scans the stations and responds in a particular manner upon engaging each strand advancing substantially normally. A transducer is responsive to the feeler engaging a normally advancing strand, for actuating an electronic switch and providing a signal. More particularly, a tender patrols the stations and the feeler is mounted on the tender, with the transducer responding to a particular vibration of the feeler for regulating operation of the tender.

These and other objects and advantages of the invention will be apparent from the following description and the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a fragmentary, schematic plan view of a plurality of spinning stations of a spinning frame, and a portion of a strand detector system on a tender which patrols and services the stations, with parts broken away and removed and other parts omitted for clearer illustration;

FIG. 2 is an enlarged, fragmentary, schematic, sectional elevational view'taken generally along the line 2-2 in FIG. 1; and

FIG. 3 is an electrical diagram of the strand detector system partially shown in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I of the drawing a spinning frame 10 has a bank of side by side spinning stations 12, with a similar bank of stations (not shown) on the opposite side of the spinning frame 10. With reference to FIGS. 1 and 2, each spinning station 12 includes a supply of roving 14 having an unwinding end in the form of a;

strand 16 which passes first through a guide eye 18 and then through a set of drafting rolls 20. As the strand l6 emerges from the drafting rolls 20 it is spun into yarn and passes through a centering eye 22 (FIG.2) directly above a rotating bobbin 24 on which the strand 16 of yarn is wound. From the centering eye 22 the strand 16 passes through a traveler 26 on a traveler ring 28 suitably mounted on a ring rail 30. As shown in FIG. 2, a rotating spindle 32 isjoumaled on a fixed portion of the spinning frame 10 and carries the rotating bobbin 24. Movement of the traveler 26 about the ring 28 causes the strand 16 to balloon, as at 34, between the centering eye 22 and the traveler 26, and this ballooning is carried, in lesser intensity, from the centering eye 22 toward the drafting rolls 20, as at 36.

With reference to FIGS. 1 and 2, a self-propelled tender 40 has wheels 42 (FIG. 2) received on tracks 44 for patrolling the spinning stations 12. The tender 40 stops at any spinning station 12 requiring servicing.

As is more fully discussed in the previously noted United States patent various sensors on the tender 40 determine the condition of each spinning station l2.as the tender is patrolling the stations. When a station 12 requires servicing a control system on the tender initiates a work cycle of the tender by first stopping the tender at the station. Upon stopping mechanism carried by the tender doffs the bobbin 24 at the station, dons an empty bobbin core 46 onto the spindle 32 and starts the strand l6 winding onto the bobbin core. The tender 40 may patrol the spinning stations 12 in any desired manner. For example it may move back and forth past the stations of one of the banks with another tender patrolling the other bank of stations, or one tender may travel about the ends of one or more spinning frames and patrol both banks of stations. An ends down sensor or detector 48 (FIGS. 1-3) determines whether or not the strands 16 are advancing normally at the stations 12 and differentiates between a normally advancing strand and a standing strand, whether taut or slack.

With reference to FIGS. 1-3, the detector 48 includes a feeler 50 or bail for engaging the normally advancing strands 16 at the stations 12 and responding thereto by being deflected in a manner causing vibration of the feeler. Upon the feeler 50 engaging a normally advancing strand 16 the resultant deflection or vibration is transmitted to a suitable transducer 52 which provides an electrical signal to an electronic switch 64 (FIG. 3). The output of the switch 64 is a signal which is fed, for example, to a control system, similar to that disclosed in the previously noted patent, for regulating operation of the tender 40 and, more particularly, for continuing patrolling operation of the tender.

The transducer 52 may be of any suitable type, for example a piezoelectric cartridge or a magnetic cartridge having either a moving or fixed magnet. Transducer 52 includes a stethescope horn 54 having a tube 56 suitably fixed to the tender 40 by a bracket 58 (FIG. 2). The tube 50 has opposite open ends, one fixed to a flared frusto-conical hollow receiver 60. The receiver 60 has a diaphragm 62 fixed across its wider free end (FIG. 3) and the feeler 50 has one or both ends secured to the diaphragm so that it may cam into engagement with and glide across the strands 16. Upon responding to a normally advancing strand 16 at a spinning station 12, the resultant vibration imparted to the bail 50 is transmitted to the diaphragm 62, and is then transmitted from the diaphgram in the form of an audible wave passing through the frusto-conical receiver 60 and the tube 56 to a suitable pick-up. The pick-up 64 is illustrated in the form of a microphone fixedly secured to the tender by a bracket 66 (FIGS. 1 and 2).

As shown in FIG. 3, the electrical signal generated by the pick-up 64 is AC coupled, as at 68, to an amplifier 70 from which a signal passes through a threshold detector 72 which differentiates between a signal produced by a normally advancing strand l6 and a stationary or slack strand.

While this invention has been described with reference to a particular embodiment in a particular environment, various changes may be apparent to one skilled in the art and the invention is therefore not to be limited to such embodiment or environment except as set forth in the appended claims.

What is claimed is:

1. Apparatus for sensing the condition of a strand processing position which is operable to advance a strand in a path therealong comprising, strand sensing means movable relative to said strand processing position, said sensing means including strand engaging means operable to intersect the path of said strand as said sensing means is moved relative thereto, said strand engaging means being connected to means for producing an acoustical signal in response to engagement of said strand engaging means with said strand, transducer means operable to convert said acoustical signal to an electrical signal, and signal detection means operable to receive said electrical signal and produce an output signal when said electrical signal exceeds a predetermined magnitude.

2. Apparatus as set forth in claim 1 including means for amplifying said electrical signal prior to transmission of said signal to said detection means.

3. Apparatus as set forth in claim 2 wherein said signal detection means is a signal threshhold detector triggered to produce said output signal when the amplitude of the electrical signal received thereby exceeds said predetermined magnitude.

4. Apparatus as set forth in claim 1 wherein said strand engaging means is deflected in response to engagement with said strand, and said means for producing said acoustical signal operates in response to the deflection of said strand engaging means.

5.. Apparatus as set forth. in claim 1 wherein said means for producing said acoustical signal includes a diaphragm, said strand engaging means being connected with said diaphragm.

6. Apparatus as set forth in claim 1 wherein said transducer means includes a microphone arranged to receive said acoustical signal.

7. Apparatus as set forth in claim 1 including a tender movable relative to said strand processing position and operable to tend the strand at said position, said output signal being operable to control the operation of said tender.

8. Apparatus as set forth in claim 7 including means mounting said sensing means on said tender.

4 i i i i

Claims

5. Apparatus as set forth in claim 1 wherein said means for producing said acoustical signal includes a diaphragm, said strand engaging means being connected with said diaphragm.