US2420513A - Stop motion mechanism - Google Patents

Stop motion mechanism Download PDF

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US2420513A
US2420513A US687449A US68744946A US2420513A US 2420513 A US2420513 A US 2420513A US 687449 A US687449 A US 687449A US 68744946 A US68744946 A US 68744946A US 2420513 A US2420513 A US 2420513A
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shaft
yarn
tension
uprising
arm
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US687449A
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Charles W Arrowood
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    • DTEXTILES; PAPER
    • D04BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04BKNITTING
    • D04B35/00Details of, or auxiliary devices incorporated in, knitting machines, not otherwise provided for
    • D04B35/10Indicating, warning, or safety devices, e.g. stop motions

Definitions

  • V Fi ure 3 is a vertical sectional view taken along the line 3, 3' in Figure land showing the parts inthe same positionasshown in Figure 2;
  • Figure 4 is a view'similar to Figure 2 ,”but showing "the parts in” operative position, with increased tension appliedto'the yarn;
  • Figure 6 is a-verticalsectional-view taken along the same line as Figure 3, but showing the parts in the position they-willoccupy when too great a tension is present in the yarn as it comes from thecone;
  • Y a Y Figure- 7- is a top plan view of the apparatus shown in * Figure *1 with a portion thereof in sect n: ,1 i t t
  • Figure 8 isa detail looking down on the top of Figure and showing how the thread rides outwardly to release the stop motion drop wire.
  • the ⁇ numeral l0 lindicates'anarm or bracket which isusually attached to the uprising shaft of -thecone and tension rack on a knitting machine.
  • the cones of yarn are disposed on suitable arms on the rack below the level of the arms lll' and suitable guide arms having eyes therein are disposed above the brackets I0 throughf which the yarn is passed, after pass feed fingers oi the uprising member l3 which projects laterally at its upper end, as at 14, andhas a slot 15 therein.
  • Mounted in the uprising member 13 is a bolt l fi having slidably and loosely mounted' thereon movable tension discs I! and I8 normally pressed against collar I9 I by means of a compression spring 20.
  • the bolt [6 has surrounding the same a porcelain sleeve 2
  • the outer end o f'bolt l-Bisthreded and has threadably mounted thereon a pair of nuts 23 and 24 for regulating the compression present in spring 20 for regulating the amount of pressure applied to the tension disc I8,1one nut 23 serving to regulate this'tension and the nut 24 is really a lock nut for locking the nut 23 in position.
  • an uprising member 21 Rotatably mounted in members I3 and 21 is a shaft 30 having an upturned portion 3
  • the shaft 30 has aco'l1ar'3l adjustably secured thereon and having extendingtherefrom a screw and contact member. This .contact member 38' is adaptedat times to engage a fixed contact 39 secured on a binding post 34 mounted in an insulating sleeve '35 disposed in arm Ill.
  • the arms l'llare grounded, forming one side of an electrical circuit and binding post 34 has secured thereto a wire 36 forming the other side of; the circuit, saidcircuit leading to a suitable stop motion,fsignallight, alarm bell and the like.
  • Wire 36 would necessarily lead to the stop motion apparatusof the machine and could also lead through. suitable alarm mechanisms or signalling mechanisms as desired; r
  • a shaft 40 Oscillatably mounted in the members 13 and 21 is a shaft 40 having an outturned portion or arm 42 provided witha, hook 43 on one end.
  • the other end of shaft 40 has an uprising curved end portion 44 adapted at times to move in between the tension discs l1 and I8 and relieve the tension on the yarn or strand when it becomes hung on the cone or fails to be fed freely.
  • oscillatabl mountedin brackets [37 and 2'l,i s a shaft 50 having an uprising portion5l and alaterally projecting portion 52 and an angular end portion 53.
  • the shaft 50 Near its other end the shaft 50 has a collar 55 secured thereon provided with an arm 56 to which the lower end of a tension spring 51 is secured, the tension spring projecting upwardly and passing through a horizontal portion 58 of member 21.
  • Portion 58 has pivotally mounted as at 60 a swingable blade member 6
  • This shaft 50 has a laterally projecting arm 62 which passes through loop portion 43 and then projects upwardly and then downwardly forming a broad notch 64 through which the strand of yarn passes after it is passed through the apparatus on the right hand side of Figure 1, and after it has gone through a suitable guide eye disposed thereabove.
  • the arm 62 will be raised upwardly from the position shown in Figure 3 to the position shown in Figure 6, which will cause th portion 44 to move in between the tension discs 11 and I8 and relieve the tension on the yarn.
  • the pull of the yarn will cause it to move outwardly on the angular end portion 53 of portion 52 and will thus push the yarn or strand from between the projection l4 and portion 33 and free it from the portion 33 and allow the portion 33 to pass through slot l5 and allow shaft 36 to oscillate and swing to the position shown in Figure 5, which will cause contact to be made between contact screw 38 and the fixed contact 39 and stop the machine.
  • a stop motion mechanism through which a strand of yarn is adapted to be passed comprising an uprising fixed member having a laterally projecting portion provided with an open ended slot, a, second uprising member disposed in spaced relation to the first uprising member, a shaft oscillatably mounted in the two uprising members and having an upturned portion provided with a horizontal projecting portion adapted to move through said slot, and having a contact member near its other end, a fixed contact adjacent the contact on the shaft, a pair of tension discs on the first uprising member, through which a strand of yarn is adapted to be passed, said strand of yarn being adapted to be passed between the lateral projection on the first uprising member and the horizontally projecting portion on the first named shaft, a second shaft oscillatably mounted in the uprising members and having an uprising portion adapted to pass between the tension discs and having at its other end an outturned portion, a third oscillatable shaft mounted in the uprising members and having portions bent to project above a
  • a stop motion device adapted to have a strand passed therethrough and to be affixed to a suitable machine processing the strand comprising an electrical circuit, having a contact, an oscillatable shaft having a contact thereon, normal tension on the strand serving to hold the oscillatable shaft in a position to where its contact will not engage the fixed contact, a pair Of tension disks, a second oscillatable shaft having means on one end for passing between the tension discs to relieve tension on the yarn and having a laterally extending portion on its other end, a third oscillatable shaft having a portion on one end adapted to engage a strand, and having an arm on its other end adapted to engage the arm on one end of the second named shaft, excessive tension in the yarn serving to guide the strand out of contact with the arm on the first named shaft to allow it to oscillate to cause its contact to engage the fixed contact to stop the machine and excessive tension on the arm on the third named oscillatable shaft serving to move the second named oscillatable shaft to cause the uprising curved end portion on one end
  • Stop motion means through which a strand of yarn is adapted to be passed and having an electrical circuit provided with a fixed contact, an oscillatable shaft having a contact thereon adapted to engage the fixed contact, means on the first-named shaft for engaging the yarn to hold the shaft in a position to where its contact will not engage the fixed contact, a second oscillatable shaft, a pair of tension discs through which the yarn is passed, portion on one end of the second sh'aft passing in between the tension discs for relieving tension on the yarn, the second shaft having an arm on its other end, a third oscillatable shaft having an uprising portion on one end provided with a sloping surface adapted to engage the strand as it passes through the apparatus, the third shaft having an arm on its other end passing below the arm on the other end of the second shaft, excessive tension on the yarn serving to cause the portion on the first end of the second shaft to pass between the tension discs to decrease the tension on the yarn and also serving to guide the yarn off of the first arm on the first named shaft to release the yarn
  • a stop motion apparatus to be associated with a knitting machine and the like, comprising an arm, a pair of vertically disposed or uprising members disposed in spaced relation on said arm, first, second and third shafts oscillatably mounted in said vertically disposed members, the first of said vertically disposed members having a lateral projection provided with a slot near its upper end and having a pair of tension discs mounted thereon, the yarn being adapted to be passed through the tension discs and adjacent the laterally projecting portion on the first vertically disposed member, the first shaft having an upturned portion on the end thereof provided with a horizontal portion and adapted to pass through said slot in the lateral projection on the first named vertically disposed member and the passage of the yarn being adapted to prevent the first shaft from oscillating, the second named shaft having an uprising, curved end portion on one end thereof adapted to pass between the tension discs and having a laterally projecting arm on its other end, the third shaft having an upwardly projecting arm adjacent the first upturned portion and having a, s

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Knitting Machines (AREA)

Description

y 13, 1947' c. w. ARROWOOD 13 STOP MOTION MECHANI SM Filed July 31, 1946 2 Sheets-Sheet 1 CHARLES Ml Aeeowoop awe/whom y 3, 1947. c. w. ARRbwopD 13 STOP MOTION MECHANISM I Filed July 51, 194% 2 Sheets-Sheet 2 so CHARLES MAezowooa 9 40 I v 1o I Patented May 13, 1947 STATES PATENT o c-E;
2,420,513. STOP MOTION MEoHAms u Charles drrowood, bliarlotte, 0. Application July 31, 1945, se ial 651449 4 Claims. (Cl. 66-463) Eigurez .is a vertical sectional viewta'ken along.
the line '2- -'2and showing the parts in the position when normal tension is applied'to the y rn?" i V Fi ure 3 is a vertical sectional view taken along the line 3, 3' in Figure land showing the parts inthe same positionasshown in Figure 2;
' Figure 4 is a view'similar to Figure 2 ,"but showing "the parts in" operative position, with increased tension appliedto'the yarn;
Figur e'S is a'view similar to Figure 4, but showing theparts in the position they will cupywhen too great a tension is'being applied to the yarn, such as by its hanging up on the cone' and notproperly shedding from the cone;
Figure 6 is a-verticalsectional-view taken along the same line as Figure 3, but showing the parts in the position they-willoccupy when too great a tension is present in the yarn as it comes from thecone; Y a Y Figure- 7-is a top plan view of the apparatus shown in *Figure *1 with a portion thereof in sect n: ,1 i t t Figure 8 isa detail looking down on the top of Figure and showing how the thread rides outwardly to release the stop motion drop wire.
Rf erringmore specifically to the drawings, the {numeral l0 lindicates'anarm or bracket, which isusually attached to the uprising shaft of -thecone and tension rack on a knitting machine." The cones of yarn are disposed on suitable arms on the rack below the level of the arms lll' and suitable guide arms having eyes therein are disposed above the brackets I0 throughf which the yarn is passed, after pass feed fingers oi the uprising member l3 which projects laterally at its upper end, as at 14, andhas a slot 15 therein. Mounted in the uprising member 13 is a bolt l fi having slidably and loosely mounted' thereon movable tension discs I! and I8 normally pressed against collar I9 I by means of a compression spring 20.
The bolt [6 has surrounding the same a porcelain sleeve 2| on which the tension discs I! and I8 ware loosely and slidably m'ountd and these tension discs have an opening therein ofgreater diameter than the sleeve 21, so that they can not only slide but have swinging 'movement on the sleeve 2l. The outer end o f'bolt l-Bisthreded and has threadably mounted thereon a pair of nuts 23 and 24 for regulating the compression present in spring 20 for regulating the amount of pressure applied to the tension disc I8,1one nut 23 serving to regulate this'tension and the nut 24 is really a lock nut for locking the nut 23 in position. Y
Also uprising from arm I 0 is an uprising member 21. Rotatably mounted in members I3 and 21 is a shaft 30 having an upturned portion 3| immediately to the right of member l3 in Figure 1, which has an inturned portion" 32 'near its upper end and a laterally and outwardly or horizontally projecting portion 33 which is adapted to have movement into and out of slot 15 in projection M. The shaft 30 has aco'l1ar'3l adjustably secured thereon and having extendingtherefrom a screw and contact member. This .contact member 38' is adaptedat times to engage a fixed contact 39 secured on a binding post 34 mounted in an insulating sleeve '35 disposed in arm Ill. The arms l'llare grounded, forming one side of an electrical circuit and binding post 34 has secured thereto a wire 36 forming the other side of; the circuit, saidcircuit leading to a suitable stop motion,fsignallight, alarm bell and the like. Wire 36 would necessarily lead to the stop motion apparatusof the machine and could also lead through. suitable alarm mechanisms or signalling mechanisms as desired; r
Oscillatably mounted in the members 13 and 21 is a shaft 40 having an outturned portion or arm 42 provided witha, hook 43 on one end. The other end of shaft 40 has an uprising curved end portion 44 adapted at times to move in between the tension discs l1 and I8 and relieve the tension on the yarn or strand when it becomes hung on the cone or fails to be fed freely. Also oscillatabl mountedin brackets [37 and 2'l,i s a shaft 50 having an uprising portion5l and alaterally projecting portion 52 and an angular end portion 53. Near its other end the shaft 50 has a collar 55 secured thereon provided with an arm 56 to which the lower end of a tension spring 51 is secured, the tension spring projecting upwardly and passing through a horizontal portion 58 of member 21. Portion 58 has pivotally mounted as at 60 a swingable blade member 6|, which is adapted to enter the folds of tension spring 51 at any desired point to regulate the tension present in spring 51.
This shaft 50 has a laterally projecting arm 62 which passes through loop portion 43 and then projects upwardly and then downwardly forming a broad notch 64 through which the strand of yarn passes after it is passed through the apparatus on the right hand side of Figure 1, and after it has gone through a suitable guide eye disposed thereabove.
Method of oneration As before stated, there is an arm ill for each strand of yarn being knitted in the knitting machine, and the yarn or strand I2 is passed up between the tension discs I1 and I8 and in front of the horizontally projecting portion 33 of upturned portion 3|, which prevents the horizontally projecting portion 33 from going through the slot [5. The yarn thus holds the parts in the position shown in Figures 1 and 2 and it goes up through a suitable eye and back under the flat V-shaped portion of arm 62 and then goes upwardly again through another guide eye on its way to the feed fingers of the machine. This holds the parts in the position shown in Figure 3, and Figures 4 and '7 also show the parts in normal operating position. Now, in case a strand [2 breaks and allows the horizontally projecting portion 33 to swing through slot l5 and occupy the position shown in Figure 5, which will cause the uprising contact 38 to move over against fixed contact 39 to close the circuit to operate the stop motion mechanism of the machine and also to give a suitable signal or alarm if desired. In other words, the contact 38 will move over to the position shown in Figure 6. Now, while the yarn is running under normal tension, the parts will be in the position shown in Figure 4, that is, the end portion 44 on shaft 48 will be moved in between the tension discs I! and IS a slight amount, not far enough to spread them apart. Now, in case the let-off of the yarn from the cone is hindered in any way, and there is greater tension on the yarn than normal, the arm 62 will be raised upwardly from the position shown in Figure 3 to the position shown in Figure 6, which will cause th portion 44 to move in between the tension discs 11 and I8 and relieve the tension on the yarn. In case the tension is not relieved, the pull of the yarn will cause it to move outwardly on the angular end portion 53 of portion 52 and will thus push the yarn or strand from between the projection l4 and portion 33 and free it from the portion 33 and allow the portion 33 to pass through slot l5 and allow shaft 36 to oscillate and swing to the position shown in Figure 5, which will cause contact to be made between contact screw 38 and the fixed contact 39 and stop the machine.
In the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only, and not for purposes of limita- 4 tion, the scope of the invention being defined in the claims.
I claim:
1. A stop motion mechanism through which a strand of yarn is adapted to be passed, comprising an uprising fixed member having a laterally projecting portion provided with an open ended slot, a, second uprising member disposed in spaced relation to the first uprising member, a shaft oscillatably mounted in the two uprising members and having an upturned portion provided with a horizontal projecting portion adapted to move through said slot, and having a contact member near its other end, a fixed contact adjacent the contact on the shaft, a pair of tension discs on the first uprising member, through which a strand of yarn is adapted to be passed, said strand of yarn being adapted to be passed between the lateral projection on the first uprising member and the horizontally projecting portion on the first named shaft, a second shaft oscillatably mounted in the uprising members and having an uprising portion adapted to pass between the tension discs and having at its other end an outturned portion, a third oscillatable shaft mounted in the uprising members and having portions bent to project above a lateral projection on the first named uprising member and having an outwardly and angularly directed member against which the yarn is adapted to contact on its upward travel, excessive tension in the yarn causing it to move out the laterally and angularly extending portion on the third named shaft to push the yarn from between the horizontally projecting portion on the first named shaft and the laterally extending portion on tht first uprising member to allow the first named shaft to oscillate, the fixed contact being adapted to be contacted by the contact on the first named shaft to close a circuit and stop the machine with which the stop motion is associated, parting of the yarn allowing the first named shaft to oscillate to cause its contact to engage the fixed contact to also close the circuit and stop the machine, movement of the yarn out the angularly extending portion of the third named shaft tending to oscillate the second named shaft to relieve tension on the yarn by having its uprising curved end portion moving in between the tension discs.
2. A stop motion device adapted to have a strand passed therethrough and to be affixed to a suitable machine processing the strand comprising an electrical circuit, having a contact, an oscillatable shaft having a contact thereon, normal tension on the strand serving to hold the oscillatable shaft in a position to where its contact will not engage the fixed contact, a pair Of tension disks, a second oscillatable shaft having means on one end for passing between the tension discs to relieve tension on the yarn and having a laterally extending portion on its other end, a third oscillatable shaft having a portion on one end adapted to engage a strand, and having an arm on its other end adapted to engage the arm on one end of the second named shaft, excessive tension in the yarn serving to guide the strand out of contact with the arm on the first named shaft to allow it to oscillate to cause its contact to engage the fixed contact to stop the machine and excessive tension on the arm on the third named oscillatable shaft serving to move the second named oscillatable shaft to cause the uprising curved end portion on one end thereof to pass between the tension discs to relieve excessive tension on the yarn.
3. Stop motion means through which a strand of yarn is adapted to be passed and having an electrical circuit provided with a fixed contact, an oscillatable shaft having a contact thereon adapted to engage the fixed contact, means on the first-named shaft for engaging the yarn to hold the shaft in a position to where its contact will not engage the fixed contact, a second oscillatable shaft, a pair of tension discs through which the yarn is passed, portion on one end of the second sh'aft passing in between the tension discs for relieving tension on the yarn, the second shaft having an arm on its other end, a third oscillatable shaft having an uprising portion on one end provided with a sloping surface adapted to engage the strand as it passes through the apparatus, the third shaft having an arm on its other end passing below the arm on the other end of the second shaft, excessive tension on the yarn serving to cause the portion on the first end of the second shaft to pass between the tension discs to decrease the tension on the yarn and also serving to guide the yarn off of the first arm on the first named shaft to release the yarn from the first named shaft to allow it to oscillate to cause its contact to engage the fixed contact to close a circuit to stop the machine with which the apparatus is associated.
4. A stop motion apparatus to be associated with a knitting machine and the like, comprising an arm, a pair of vertically disposed or uprising members disposed in spaced relation on said arm, first, second and third shafts oscillatably mounted in said vertically disposed members, the first of said vertically disposed members having a lateral projection provided with a slot near its upper end and having a pair of tension discs mounted thereon, the yarn being adapted to be passed through the tension discs and adjacent the laterally projecting portion on the first vertically disposed member, the first shaft having an upturned portion on the end thereof provided with a horizontal portion and adapted to pass through said slot in the lateral projection on the first named vertically disposed member and the passage of the yarn being adapted to prevent the first shaft from oscillating, the second named shaft having an uprising, curved end portion on one end thereof adapted to pass between the tension discs and having a laterally projecting arm on its other end, the third shaft having an upwardly projecting arm adjacent the first upturned portion and having a, sloping portion thereon adapted to contact the yarn adjacent the point where it is contacted by the laterally projecting portion on the first arm, the third shaft having an arm on its other end adapted to be passed below the arm on the other end of the second shaft, and beneath which the strand of yarn is adapted to be passed so that increased tension on the yarn will cause the uprising curved end portion on the first named end of the third shaft to pass between tension discs to relieve the tension of the yarn when it is above normal, the sloping portion on the first named arm on the second named sh'aft guiding the yarn outwardly when excessive tension appears to push it from contact with the laterally projecting portion on the upwardly projecting arm on the first shaft to allow it to pass through the slot in the horizontally projecting portion on the first vertically disposed member to allow the first named shaft to oscillate by gravity to cause its contact to engage the fixed contact to stop the machine, and tension means on the third shaft for pressing its sloping portion into engagement with the strand of yarn.
CHARLES W. ARROWOOD.
US687449A 1946-07-31 1946-07-31 Stop motion mechanism Expired - Lifetime US2420513A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2467366A (en) * 1947-01-31 1949-04-19 Charles W Arrowood Electrical stop motion for knitting machines
US2467952A (en) * 1949-04-19 Antonevich
US2468611A (en) * 1947-05-13 1949-04-26 Charles W Arrowood Electrical stop motion for knitting machines
US2745609A (en) * 1953-10-14 1956-05-15 Lermont Basil Constant force yarn tensioning means
US2952890A (en) * 1954-10-25 1960-09-20 Stanier Harold Yarn control device
US3755864A (en) * 1972-02-23 1973-09-04 Singer Co Yarn tension controllers and slub catchers

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2467952A (en) * 1949-04-19 Antonevich
US2467366A (en) * 1947-01-31 1949-04-19 Charles W Arrowood Electrical stop motion for knitting machines
US2468611A (en) * 1947-05-13 1949-04-26 Charles W Arrowood Electrical stop motion for knitting machines
US2745609A (en) * 1953-10-14 1956-05-15 Lermont Basil Constant force yarn tensioning means
US2952890A (en) * 1954-10-25 1960-09-20 Stanier Harold Yarn control device
US3755864A (en) * 1972-02-23 1973-09-04 Singer Co Yarn tension controllers and slub catchers

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