US3689716A - Magnetic stop motion device - Google Patents

Magnetic stop motion device Download PDF

Info

Publication number
US3689716A
US3689716A US139173A US3689716DA US3689716A US 3689716 A US3689716 A US 3689716A US 139173 A US139173 A US 139173A US 3689716D A US3689716D A US 3689716DA US 3689716 A US3689716 A US 3689716A
Authority
US
United States
Prior art keywords
magnet
magnets
shaft
switch
yarn
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US139173A
Inventor
Gregory Csurgay
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
U S TEXTILE MACHINE CO
Original Assignee
U S TEXTILE MACHINE CO
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by U S TEXTILE MACHINE CO filed Critical U S TEXTILE MACHINE CO
Application granted granted Critical
Publication of US3689716A publication Critical patent/US3689716A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H36/00Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding
    • H01H36/0073Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding actuated by relative movement between two magnets
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B65CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65HHANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H63/00Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package
    • B65H63/02Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material
    • B65H63/024Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material responsive to breakage of materials
    • B65H63/028Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material responsive to breakage of materials characterised by the detecting or sensing element
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B65CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65HHANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2701/00Handled material; Storage means
    • B65H2701/30Handled filamentary material
    • B65H2701/31Textiles threads or artificial strands of filaments

Definitions

  • ABSTRACT 52 US. Cl ..200/61.18, 335/207 A feeler arm for textile thread which activates a p 51 Int. Cl. ..LB65h 25/14 motion device y magnetic means-
  • the magnets [58] Field of Search 200/6113 6L1 8, 153 T 47; operatively engage with a lever arm Of a microswitch.
  • the magnetic means may constitute a tWO magnet 01' a three magnet system and by proper proportioning will achieve the required rotating torque and axial move- [56] References cued ment to actuate the microswitch and thereby stop the UNrrED STATES PATENTS y delivery syst 3,170,052 2/1965 Hajos ..200/61.4l X 2 Claims, 8 Drawing Figures minnow 5 m2 3589716 INVENTOR ATTO R N EYE PATENTEDSEP m 3.689.716
  • This invention relates to a stop motion device for textile yarns which utilizes magnets for activating a microswitch to thereby shut ofi yarn delivery to the mechanism.
  • the torque produced by the magnets is adjustable by changing the distance between the magnets.
  • the magnets are so constructed and arranged that rotating torque, as well as a push and pull effect is achieved.
  • Another object of the present invention is to provide a stop motion device which is inexpensive to manufacture yet is reliably effective for the purposes intended.
  • FIG. 1 is a perspective view of a magnetic stop motion device for yearn processing machine constructed in accordance with the teachings of the present invention
  • FIG. 2 is a partial top plan view of the magnetic stop motion device showing the microswitch lever arm depressed
  • FIG. 3 is a front elevational view, partly in section, of the magnetic stop motion device showing the relative position of the thread supporting arm sown in FIG. 2;
  • FIG. 4 is another partial side elevational view of the magnetic stop motion device similar to FIG. 2 in which the microswitch lever arm is not depressed;
  • FIG. 5 is a front elevational view of the structure shown in FIG. 4, partly in section, showing the relative position of thread supporting arm illustrated in FIG. 4;
  • FIG. 6 is a sectional view taken along the line 6-6 of FIG. 4;
  • FIG. 7 is a partial sectional and partial elevational view of another embodiment of the present invention in which the lever arm of the microswitch has depressed the microswitch;
  • FIG. 8 is a view similar to FIG. 7 in which the lever arm has not depressed the microswitch, and the thread supporting arm is in another position.
  • a yarn processing machine may have a series of magnetic stop motion devices of the type shown in FIGS. l-6.
  • the stop motion device comprises a frame 10 having a U-shaped subframe 10a.
  • a conventional microswitch 12 having an actuator button 14.
  • the microswitch 12 is also provided with a pivoting actuator lever arm 16.
  • Rotatable and slidable in the bushings 18 and 20 of subframe 10a is a shaft 22.
  • a magnet 24 Secured to one leg of the subframe 10a is a magnet 24, having poles as illustrated. It will be noted that the shaft 22 passes freely through magnet 24 as well as bushings l8 and 20 of the subframe 10a.
  • another magnet 26 Secured to the shaft 22 and spaced from the magnet 24 is another magnet 26 with poles as indicated. Magnet 26 is mounted to both rotate and move axially toward and away from magnet 24.
  • magnet 24 is provided with a stop member 28 forming a sleeve on the shaft 22.
  • one end of shaft 22 is provided with a laterally projecting thread supporting arm 30.
  • This arm has a lateral extension 30a which engages the tensioned yarn.
  • magnet 26 is held in a position where like poles substantially face each other or at least are in nearer vicinity than unlike poles.
  • This said position X of magnet 26 results in an axial repelling force which acts between magnets 26 and 24.
  • Magnet 24 being anchored to subframe 10a and magnet 26 being anchored to freely rotatable and slidable shaft 22, this shaft will move axially in the direction away from magnet 24 and from switch actuator lever arm 16. This maintains closed position of the contacts of switch 10 and allows current to flow to the yarn processing machine.
  • the magnet 26 When the yarn breaks, the magnet 26 will rotate relative to magnet 24, due to said magnetic torque, thereby turning the thread supporting arm 30 and swinging it upwardly. When the rotation of the magnet 26 has reached such point that the opposite poles of magnets 24 and 26 are aligned, the magnet 26 is attracted toward the magnet 24 and closes the gap a, shown in FIG. 4 to the reduced gap b, illustrated in FIG. 2. As shown in FIGS. 3 and 5, the yarn supporting arm 30 moves from the position X shown in FIG. 5 to the position Y shown in FIG. 3. In this position Y, the pivoting actuating lever arm 16 is depressed and, consequently, the button 14 of the microswitch is also depressed, thereby opening the electrical circuit of the yarn processing machine. In the resulting position of the microswitch shown in FIG. 2, the switch has been activated in a manner to open the electrical circuit of the yarn processing machine and therefore render said machine inoperative.
  • the magnet 24 is fixed to the subframe 10a by means of an adhesive 32.
  • the magnet 26 is secured to the shaft 22 by means of fixed sleeve 34.
  • FIGS. 7 and 8 disclose a further embodiment of the present invention incorporating three magnets, 44, 46 and 48 respectively.
  • the aforesaid magnets are mounted in a frame 50 which is provided with guides 52 and 54 for the adjustable magnet 48.
  • the adjustability of magnet 48 is accomplished by means of screw 56 rotatable in tapped hole 58 in the frame 50 and secured at one end to the magnet 48.
  • the screw 56 is provided with a knurled knob 60 which can be turned in order to move the magnet axially within the guides 52 and 54 in a direction toward or away from magnet 46.
  • Magnet 46 is further provided with a thread supporting arm 30 and magnet 44 is secured to the pivoting actuating lever arm 16 of the microswitch 12.
  • the present device is small and compact and therefore a multiplicity of these devices may be used on yarn processing machines for each of the yarns. This arrangement results in an effective magnetic stop motion device arrangement for the machine.
  • a magnetic stop motion device for a yarn processing machine comprising a switch, at least two spaced magnets, means mounting said magnets whereby one of said magnets is rotatable and axially movable with respect to the other magnet, said one magnet being provided with a shaft that passes through the other of said magnets, one end of said shaft being inoperative engagement with said switch, a thread supporting arm on said shaft being held by yarn tension at a location whereby said magnets repulse each other and said one magnet having said shaft is thereby axially moved away from the other magnet to a position in which said switch closes the electrical circuit of said yarn processing machine, and when said yarn breaks said arm and said one magnet rotate to a position whereby said magnets attract each other and thereupon axially move said shaft to operate said switch and open the electrical circuit of the yarn processing machine.

Abstract

A feeler arm for textile thread which activates a stop motion device by magnetic means. The magnets operatively engage with a lever arm of a microswitch. The magnetic means may constitute a two magnet or a three magnet system and by proper proportioning will achieve the required rotating torque and axial movement to actuate the microswitch and thereby stop the yarn delivery system.

Description

United States Patent Csurgay 1 Sept. 5, 1972 [54] MAGNETIC STOP MOTION DEVICE 3,330,016 7/1967 Smith et al ..200/6l.l8 X 3,397,372 8/1968 Maxwell ..335/206 X F L [72] Invent gg Csurgay auderdale 3,234,341 2/1966 Jurczyk ..200/47 2,566,824 9/1951 Carlson ..200/47 [73] Assignee: U.S. Textile Machine Company,
Scranton, Pa. Primary Examiner-Robert K. Schaefer Assistant ExaminerM. Ginsburg [22] Flled' Apnl 1971 Attorney-Nolte and Nolte [21] Appl. No.2 139,173
[57] ABSTRACT 52 US. Cl ..200/61.18, 335/207 A feeler arm for textile thread which activates a p 51 Int. Cl. ..LB65h 25/14 motion device y magnetic means- The magnets [58] Field of Search 200/6113 6L1 8, 153 T 47; operatively engage with a lever arm Of a microswitch. The magnetic means may constitute a tWO magnet 01' a three magnet system and by proper proportioning will achieve the required rotating torque and axial move- [56] References cued ment to actuate the microswitch and thereby stop the UNrrED STATES PATENTS y delivery syst 3,170,052 2/1965 Hajos ..200/61.4l X 2 Claims, 8 Drawing Figures minnow 5 m2 3589716 INVENTOR ATTO R N EYE PATENTEDSEP m 3.689.716
sum 2 or 2 mvzgyon fer om sue m B m rm ATT RNEYS MAGNETIC STOP MOTION DEVICE This invention relates to a stop motion device for textile yarns which utilizes magnets for activating a microswitch to thereby shut ofi yarn delivery to the mechanism.
It is an object of the present invention to provide a threadbreak sensor for threads which are under tension and which by the proper selection of magnets, soft steel ring, as well as the proper distances between the magnets and the steel ring, any combination of rotating torque and pull-in force can be achieved.
It is another object of the present invention to provide a threadbreak sensor or magnetic stop motion device in which the reaction time is very short, and thus the mechanism is stopped almost immediately, avoiding serious problems with the same.
It is a further object of the present invention to provide a three magnet system in which one of the magnets is adjustable. Thus, the torque produced by the magnets is adjustable by changing the distance between the magnets.
It is another object of the present invention to provide a magnetic stop motion device based on the two magnet system in which one of the magnets is provided with a shaft that is adapted to move back and forth and thereby make and break contact with the microswitch. The magnets are so constructed and arranged that rotating torque, as well as a push and pull effect is achieved.
It is a further object of the present invention to provide magnetic discs instead of magnetic bars.
It is another object of the present invention to provide a magnetic stop motion device which is small and compact and can be used in groups on machines that process a multiplicity of threads.
Another object of the present invention is to provide a stop motion device which is inexpensive to manufacture yet is reliably effective for the purposes intended.
The invention will now be further described by detailed reference to specific embodiments which are illustrated in the drawings, wherein:
FIG. 1 is a perspective view of a magnetic stop motion device for yearn processing machine constructed in accordance with the teachings of the present invention;
FIG. 2 is a partial top plan view of the magnetic stop motion device showing the microswitch lever arm depressed;
FIG. 3 is a front elevational view, partly in section, of the magnetic stop motion device showing the relative position of the thread supporting arm sown in FIG. 2;
FIG. 4 is another partial side elevational view of the magnetic stop motion device similar to FIG. 2 in which the microswitch lever arm is not depressed;
FIG. 5 is a front elevational view of the structure shown in FIG. 4, partly in section, showing the relative position of thread supporting arm illustrated in FIG. 4;
FIG. 6 is a sectional view taken along the line 6-6 of FIG. 4;
FIG. 7 is a partial sectional and partial elevational view of another embodiment of the present invention in which the lever arm of the microswitch has depressed the microswitch;
FIG. 8 is a view similar to FIG. 7 in which the lever arm has not depressed the microswitch, and the thread supporting arm is in another position.
DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION Referring to the drawings, and especially to FIGS. 1-6 thereof, a yarn processing machine (not shown) may have a series of magnetic stop motion devices of the type shown in FIGS. l-6. The stop motion device comprises a frame 10 having a U-shaped subframe 10a. Mounted on the frame 10 is a conventional microswitch 12 having an actuator button 14. The microswitch 12 is also provided with a pivoting actuator lever arm 16.
Rotatable and slidable in the bushings 18 and 20 of subframe 10a is a shaft 22. Secured to one leg of the subframe 10a is a magnet 24, having poles as illustrated. It will be noted that the shaft 22 passes freely through magnet 24 as well as bushings l8 and 20 of the subframe 10a. Secured to the shaft 22 and spaced from the magnet 24 is another magnet 26 with poles as indicated. Magnet 26 is mounted to both rotate and move axially toward and away from magnet 24. In addition, magnet 24 is provided with a stop member 28 forming a sleeve on the shaft 22.
As seen in FIGS. 1-5, one end of shaft 22 is provided with a laterally projecting thread supporting arm 30. This arm has a lateral extension 30a which engages the tensioned yarn. When the tensioned yarn exerting a minute force holds arm 30 in a down position, which is shown in FIG. 5 and designated by X, magnet 26 is held in a position where like poles substantially face each other or at least are in nearer vicinity than unlike poles. This said position X of magnet 26 results in an axial repelling force which acts between magnets 26 and 24. Magnet 24 being anchored to subframe 10a and magnet 26 being anchored to freely rotatable and slidable shaft 22, this shaft will move axially in the direction away from magnet 24 and from switch actuator lever arm 16. This maintains closed position of the contacts of switch 10 and allows current to flow to the yarn processing machine.
While magnet 26 is held in its above mentioned position X, there is also maintained a rotating torque or pair of torque forces, which torque or pair of forces tend to rotate magnet 26 back into its natural position wherein unlike poles are facing each other and the distance between them is the shortest possible distance allowed by stop member 28.
When the yarn breaks, the magnet 26 will rotate relative to magnet 24, due to said magnetic torque, thereby turning the thread supporting arm 30 and swinging it upwardly. When the rotation of the magnet 26 has reached such point that the opposite poles of magnets 24 and 26 are aligned, the magnet 26 is attracted toward the magnet 24 and closes the gap a, shown in FIG. 4 to the reduced gap b, illustrated in FIG. 2. As shown in FIGS. 3 and 5, the yarn supporting arm 30 moves from the position X shown in FIG. 5 to the position Y shown in FIG. 3. In this position Y, the pivoting actuating lever arm 16 is depressed and, consequently, the button 14 of the microswitch is also depressed, thereby opening the electrical circuit of the yarn processing machine. In the resulting position of the microswitch shown in FIG. 2, the switch has been activated in a manner to open the electrical circuit of the yarn processing machine and therefore render said machine inoperative.
As seen in FIG. 6, the magnet 24 is fixed to the subframe 10a by means of an adhesive 32. On the other hand, the magnet 26 is secured to the shaft 22 by means of fixed sleeve 34.
FIGS. 7 and 8 disclose a further embodiment of the present invention incorporating three magnets, 44, 46 and 48 respectively. The aforesaid magnets are mounted in a frame 50 which is provided with guides 52 and 54 for the adjustable magnet 48. The adjustability of magnet 48 is accomplished by means of screw 56 rotatable in tapped hole 58 in the frame 50 and secured at one end to the magnet 48. The screw 56 is provided with a knurled knob 60 which can be turned in order to move the magnet axially within the guides 52 and 54 in a direction toward or away from magnet 46. Magnet 46 is further provided with a thread supporting arm 30 and magnet 44 is secured to the pivoting actuating lever arm 16 of the microswitch 12. In the relative positions of the magnets 44, 46 and 48, as shown in FIG. 8, there is magnetic torque acting on magnet 46 and said torque is tending to rotate magnet 46 into position shown in FIG. 8. In the position of FIG. 7 lever 16 is moved toward magnet 46 by means of magnetic attraction from magnet 44. Switch actuator button 14 is depressed and current through switch 12 is interrupted. Thread supporting arm 30 is magnetically moved to the position shown in FIG. 7 for lack of yarn force to hold it as shown in FIG. 8. The arrangement shown in FIGS. 7 and 9 is desirable if the tension on the yarn is very light, for example in order of gms. In that case, the magnet 48 is moved away from the magnet 46 by means of screw 56, thereby reducing the possibility of the magnetic force overcoming the force of the yarn tension on the arm 30. That condition results in the rotation of the magnet 46 to a position whereby the microswitch 12 is actuated without the yarn being broken.
It is to be noted that the present device is small and compact and therefore a multiplicity of these devices may be used on yarn processing machines for each of the yarns. This arrangement results in an effective magnetic stop motion device arrangement for the machine.
What is claimed is:
1. A magnetic stop motion device for a yarn processing machine comprising a switch, at least two spaced magnets, means mounting said magnets whereby one of said magnets is rotatable and axially movable with respect to the other magnet, said one magnet being provided with a shaft that passes through the other of said magnets, one end of said shaft being inoperative engagement with said switch, a thread supporting arm on said shaft being held by yarn tension at a location whereby said magnets repulse each other and said one magnet having said shaft is thereby axially moved away from the other magnet to a position in which said switch closes the electrical circuit of said yarn processing machine, and when said yarn breaks said arm and said one magnet rotate to a position whereby said magnets attract each other and thereupon axially move said shaft to operate said switch and open the electrical circuit of the yarn processing machine.
2. The combination as claimed in claim 1 further comprising a mounting for said magnets in the form of a frame, said one of the magnets being rigidly fixed to said shaft and mounted in said frame, said thread s2 porting arm being mounted on one end of said sh t,
the other end of the shaft passing through the other of said magnets and said frame and axially movable to operatively engage said switch.

Claims (2)

1. A magnetic stop motion device for a yarn processing machine comprising a switch, at least two spaced magnets, means mounting said magnets whereby one of said magnets is rotatable and axially movable with respect to the other magnet, said one magnet being provided with a shaft that passes through the other of said magnets, one end of said shaft being inoperative engagement with said switch, a thread supporting arm on said shaft being held by yarn tension at a location whereby said magnets repulse each other and said one magnet having said shaft is thereby axially moved away from the other magnet to a position in which said switch closes the electrical circuit of said yarn processing machine, and when said yarn breaks said arm and said one magnet rotate to a position whereby said magnets attract each other and thereupon axially move said shaft to operate said switch and open the electrical circuit of the yarn processing machine.
2. The combination as claimed in claim 1 further comprising a mounting for said magnets in the form of a frame, said one of the magnets being rigidly fixed to said shaft and mounted in said frame, said thread supporting arm being mounted on one end of said shaft, the other end of the shaft passing through the other of said magnets and said frame and axially movable to operatively engage said switch.
US139173A 1971-04-30 1971-04-30 Magnetic stop motion device Expired - Lifetime US3689716A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US13917371A 1971-04-30 1971-04-30

Publications (1)

Publication Number Publication Date
US3689716A true US3689716A (en) 1972-09-05

Family

ID=22485423

Family Applications (1)

Application Number Title Priority Date Filing Date
US139173A Expired - Lifetime US3689716A (en) 1971-04-30 1971-04-30 Magnetic stop motion device

Country Status (1)

Country Link
US (1) US3689716A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3940725A (en) * 1974-02-08 1976-02-24 Alarm Device Manufacturing Co. Switching apparatus
FR2323620A1 (en) * 1975-09-15 1977-04-08 Peyer Siegfried Textile machine fibre monitoring equipment - has magnet on lever opposite stationary adjustable magnet
US20100231334A1 (en) * 2007-09-14 2010-09-16 Carpenter William N Magnetically operated electrical switch

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2566824A (en) * 1950-10-28 1951-09-04 Gale K Carlson Limit switch
US3170052A (en) * 1961-08-17 1965-02-16 Hydraxtor Company Magnetically restorable sensing switch
US3234341A (en) * 1961-06-15 1966-02-08 Montgomery Elevator Electrical switching device with retractable actuator
US3330016A (en) * 1965-07-21 1967-07-11 Deering Milliken Res Corp Warper stop motion
US3397372A (en) * 1965-11-08 1968-08-13 Palmer M. Maxwell Proximity-magnetic means for operating microswitches

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2566824A (en) * 1950-10-28 1951-09-04 Gale K Carlson Limit switch
US3234341A (en) * 1961-06-15 1966-02-08 Montgomery Elevator Electrical switching device with retractable actuator
US3170052A (en) * 1961-08-17 1965-02-16 Hydraxtor Company Magnetically restorable sensing switch
US3330016A (en) * 1965-07-21 1967-07-11 Deering Milliken Res Corp Warper stop motion
US3397372A (en) * 1965-11-08 1968-08-13 Palmer M. Maxwell Proximity-magnetic means for operating microswitches

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3940725A (en) * 1974-02-08 1976-02-24 Alarm Device Manufacturing Co. Switching apparatus
FR2323620A1 (en) * 1975-09-15 1977-04-08 Peyer Siegfried Textile machine fibre monitoring equipment - has magnet on lever opposite stationary adjustable magnet
US20100231334A1 (en) * 2007-09-14 2010-09-16 Carpenter William N Magnetically operated electrical switch
US7936242B2 (en) * 2007-09-14 2011-05-03 William N Carpenter Magnetically operated electrical switch

Similar Documents

Publication Publication Date Title
US2637115A (en) Magnetic calipering device
US3322013A (en) Yarn cutting and clamping mechanism
US4039985A (en) Magnetic reed switch
US6014875A (en) Needle selection device, particularly for selecting the dial needles in circular knitting machines
US2460695A (en) Sensitive switch actuator
US4075445A (en) Thread monitoring switch for textile machines having magnet biasing lever to prevent any annoying thread flutter
US3689716A (en) Magnetic stop motion device
US5044243A (en) Cutting apparatus
US3588766A (en) Arrangement,preferably for operating contacts for switching or control devices and the like
US3963229A (en) Device for manipulating yarns
US4931758A (en) Electro-magnetic shunt trip device
US4259852A (en) Positive thread-delivery device for stripe knitting machines
US3489971A (en) Magnetically actuated limit switch
US3402269A (en) Apparatus for the detection of broken yarn and the like on textile machines
US3676990A (en) Thread-sensing device for a textile machine
JPS5768818A (en) Optical switch
GB1020086A (en) Improvements in electric stop motions for textile machines
JPS628544B2 (en)
US4713654A (en) Shaft speed monitor
US2594168A (en) Electrical stop motion for knitting machines
US3315047A (en) Filament break detector
US4811001A (en) Shaft speed monitor
US4091606A (en) Open end spinning frame with a magnetic switch for sliver feed
GB1276558A (en) Improvements in or relating to electric snap-action switches
US2933909A (en) Stop motion device for knitting machines