US2884774A

US2884774A - Releasable yarn tension device for hosiery knitting machines

Info

Publication number: US2884774A
Application number: US698298A
Authority: US
Inventors: Harold E Cox
Original assignee: WILLCRAFT HOSIERY MILLS Inc
Current assignee: WILLCRAFT HOSIERY MILLS Inc
Priority date: 1957-11-22
Filing date: 1957-11-22
Publication date: 1959-05-05
Anticipated expiration: 1976-05-05

Description

May 5, 1959 H; E. COX 2,884,774

RELEASABLE YARN TENSION DEVICE FOR HOSIERY KNITTING MACHINES' Filed Nov. 22, 1957 INVENTOR .1' =|.E1 HAROLD E. cox

ATTORNEYS United States Patent i RELEASA BLE YARN TENSION DEVICE FOR HOSIERY KNITTING MACHINES 8 Claims. (Cl. 66-146) Ilhis invention relates to knitting and m Particularly to a. releasable yarn tension device for use in circular 1 type knitting machines commonly utilized for knitting hosiery.

v -In the knitting of hosiery on a circular type knitting machine, the leg and foot'portion of the hose are knit by continuous rotation of a cylinder carrying suitable needles and the heel and toe portions of the hose are knit by oscillating the cylinder back and forth. During the rotary knitting operation, a minimum tension on theyarn is required, but during knitting of the heel and toe, it is necessary to apply appreciable tension to the .yarn and also to provide a takeup means for preventing slack. in the yarn during a portion of the oscillating "movement of the cylinder.

Hcretofore numerous types of tension devices for knitting machines and other textile apparatus have been pro- .posed and utilized and certain of these include metallic disks between which the yarn is drawn and the tension is controlled by a spring'pressing one of the disks toward the other to grip the yarn therebetween. It has been found that the yarn tends to wear grooves in such 'disks rather rapidly and the formation of such grooves result in splitting of the yarn which in turn results in the formation of inferior hose. In the majority of the presently used tensionin'g devices, it is necessary to frequently replace the tension elements due to excessive wear and "consequently, this presents a very material maintenance problem.

It is accordingly an object of'the invention to provide a releasable yarn tension device for hosiery knitting machines in which the tension may automatically be varied 1 machines in which wear of the tension elements is re- "duced to a minimum and in which such wear as may occur in no way results in damage to the yarn.

:further object of the invention is the provision of a releasable yarn tension device for hosiery knitting machines, which device may be conveniently and economically'manufactured from readily available materials 7 and conveniently applied to existing knitting machines thereby reducing the cost of maintenance of the tensioning device to a minimum.

Further objects and advantages of the invention will I be apparent from the following description taken in conjunction with the accompanying drawing wherein:

Fig. 1 is a side elevational view of a releasableyarn tension device constructed in-accordance with this invention-and showing the device imposition to a pply maximum te'nsion to the yarn;

Fig. 2 a view similar to Fig. 1 and showing the ten- 7 plastic.

surface of the friction cylinder 14.

Patented May 5, 1959 ice 2 sioning device in a position to apply minimum tension to the yarn; and

:Fig. '3 is a top plan view of the yarn tension device shown in Fig. 1.

With continued reference to the drawing, there is shown a releasable yarn tension device constructed in accordance with this invention and which may well comprise a bracket 10 mounted on the knitting machine, the bracket 10 being provided with a vertically disposed yarn guide 11 adjacent the outer end thereof. A second yarnguide 12 may also be provided on the bracket 10 at a convenient location and the operations of such guides will be later described.

A threaded stud 13 is mounted on the bracket 10' and extends transversely thereof inwardly of the yarn guide 11 and mounted on the stud 13 is a friction cylinder 14 of synthetic yieldable material, such as a suitable The cylinder 14 is fixed against rotation on the stud 13 and is held in place thereon by opposed cup members 15 and 16 which are clamped in place by a nut 17 received on the screw threaded stud 13. As will be noted from an inspection of Fig. 3, an appreciable portion of the surface of the cylinder 14 is exposed between the inner edgesof the cup shaped members 15 and 16.

An elongated ,yarn takeup member 18 is provided with an elongated central portion 19 terminating at the inner end in adown turned portion 20 which is fixed to a sleeve 21 rotatably mounted on a stud 22 secured to the bracket 10. The opposite end 23 0f the yarn takeup member 18 is down turned and isprovided with a yarn receiving eyelet 24 which, as best shown in Fig. 2, is disposed forwardly of the cylinder .14 and rearwardly of the yarn guide 11. :Also rotatably mounted on the stud 22 is an arm 25 which is fixed to the sleeve 21 for rotation therewith and the arm 25 is connected to a tension spring 26 which in turn is connected to an adjustable member 27 adjustably secured in a projection 28 of the bracket 10 by a set screw or other suitable means 29. As will be seen from an inspection of Figs. 1 and 2, the tension spring 26 tends to urge the yarn takeup member 18 upwardly to the position shown in Fig. l and when the takeup member 18 is moved downwardly to the position shown in Fig. 2, the spring 26 is placed under tension as clearly shown in Fig. #2.

A control arm 30 is mounted for free pivotal movement on the :stud 22 and the arm 30 isprovided'with a pin 31- extending transversely thereof into the path of movement of the arm 25. Also connected to the arm 30 is a control link 32 which is operated by the pattern control cam of the knitting machine. As will be seen from an inspection ofvFig..2, upon downward movement of the control link.32,the pin-31 will engage the arm 25 tomove :such arm and the ,yarn takeup member 18 downwardly from theposition shown :in Fig. 1 to the position shown in Fig. 2.

A yarn shifting rod is connected to the control link 32 with the upper end of theshifting rod 33 slidablyreceived in a guide member 34 mounted on the bracket 10 with the result that vertical movement of the control link 32 will result in a substantially vertical movement of the yarn shifting rod33. The rod 33 is provided at the upper end thereof with a yarn receiving ring 35, the purpose and operation of which will be presently described.

As best shown in Fig. 2, with the yarn takeup member 18 and the yarn receiving ring 35 on the shifting rod 33 in down position, the ring 35 and eyelet 24 are substantially in alignment with the lower circumferential Consequently, a strand of yarn 36 extending through the yarn guide 12, the ring 35, theeyelet 24 and theyarn guide .11 in the bracket 10 will .engagethe lower circumferential .sur'face of the friction cylinder 14 in substantially a point confo.ot portionby rotation of the cylinder of the knitting machine and when it is desired to knit the heel and toe portions, the control link 32 is moved upwardly which results in moving the yarn takeup member 18 upwardly to the position shown in Fig. 1 and also results in moving the yarn receiving ring. 35 on the yarn shifting rod 33 upwardly to the position shown in Fig. 1. In this position of the yarn tensioning elements, the portion 37 of the yarn 36 engaging the friction cylinder 14 is partially wrapped around the cylinder 14 to provide a line contact therewith, thereby substantially increasing tension on the yarn 36. As the cylinder of the knitting machine oscillates duringtknitting of the heel and toe portion of the hoisery, the *yarn takeup member 18 will move up and down against the action of the tension spring 26 and such movement will result in varying the length of contact between the portion 37'of the yarn 36 and the friction cylinder 14 which also results in varying the tension in the yarn 36. When it is desired to resume circular'knitting operation, the control link 32 and yarn shifting rod 33 are moved downwardly to move the yarn takeup member 18 and yarn receiving ring 35 downwardly to the position shown in Fig. 2, which results in substantially removing tension from the yarn 36.

The friction cylinder 14 provides a yieldable surface engaging the yarn 36 which imparts greater tension thereto and a hard unyielding surface and furthermore, such yieldable surface provides a greater resistance to wear and also prevents damage to the yarn during travel thereover. Also upon suflicient wear eventually occurring in the cylinder 14, in order to replace the same, it is only necessary to remove the nut 14 and the outer cup shape member 16 whereupon a new cylinder 14 may be installed and secured in place in a relatively short time thereby permitting prompt resumption of knitting operations.

It will be seen that by the above described invention, there has been provided a relatively simple and economical, yet highly efficient releasable yarn tension device for hosiery knitting machines and one which may be applied to existing machines with a of modification. 1

It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention is not limited by that which is shown in the drawing and described in the specification, but only as spaced from said guide, a. friction cylinder of synthetic yieldable material removably fixed on said stud, an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said member being down turned and provided with ayarn receiving eyelet disposed between said cylinder and said guide, spring means for urging said member upwardly toward a position with said eyelet disposed above said cylinder, a control link for holding said member down against the action of said spring means with said eyelet disposed substantially in alignment with the lowermost point on said cylinder, a yarn shifting rod slidably mounted on said bracket for substantially vertical movement, the lower end of said rod being connected'to said control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantially in alignment with the lowermost point on said cylinder when in down p sition, whereby a strand of yarn drawn through said guide,

--the lowermost point on said cylinder, at yarn shifting rod A. eyelet and ring will engage said cylinder in a substantially point contact to impart a minimum tension to the yarn and upon movement of said control link and rod upwardly, said eyelet and ring" will move upwardly to partially wrap the yarn around said cylinder to provide a line contact thereby increasing tension on the yarn.

2. A releasable yarn tension device for a hosiery knitting machine, said device comprising a horizontal bracket, a vertically disposed yarn guide on said bracket, a horizontal stud on said bracket spaced from said guide, a frictional cylinder of yieldable material removably fixed on said stud, an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said member being down turned and provided with a yarn receiving eyelet disposed between said cylinder and said guide, spring means for urging said member upwardly toward a position with said eyelet disposed above said cylinder, a control link for holding said member down against the action of said spring means with said eyelet disposed substantially in alignment with slidably mounted on said bracket for substantially vertical movement, the lower end of said rod being connected' to said control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantiallyin-alignment with the lowermost point on said cylinder when in down position, whereby a strand of yarn drawn through said guide, eyelet and ring will engage said cylinder in substantially a point contact to impart a minimum tension to the yarn and upon movement of said control link and rod upwardly, said eyelet and ring will move upwardly to partially wrap the yarn around the cylinder to provide a line contact thereby increasing tension on the yarn.

3. A releasable yarn tension device for a hosiery knitting machine, said device comprising a horizontal bracket, a yarn guide on said bracket, a horizontal stud on said bracket spaced from said guide, a friction cylinder of synthetic yieldable material removably fixed on said stud, an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said I mounted on said bracket for substantially vertical movement, the lower end of said rod being connected to said "control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantially in alignment with the lowermost point on said cylinder when in down position, whereby a strand of yarn drawn through said guide, eyelet and ring will engage said cylinderin a substantially point contact to impart a minimum tension to the yarn and upon movement of said'control link and rod upwardly, said eyelet and ring will move upwardly to partially wrap the yarn around the cylinder to provide a line contact thereby increasing tensionon the yarn.

' an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said member being down turned and provided with a yarn re- 1 ceiving eyelet disposed on one side of said cylinder,

spring means for urging said member upwardly toward a position with said eyelet disposed above said cylinder, a

control link for holding said member down against the action of said spring means with said eyelet disposed substantially in alignment with the lowermost point on said cylinder, a yarn shifting rod slidably mounted on said bracket for substantially vertical movement, the lower end of said rod being connected to said control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantially in alignment with the lowermost point on said cylinder when in down position, whereby a strand of yarn drawn through said eyelet and ring will engage said cylinder in a substantially point contact to impart a minimum tension to the yarn and upon movement of said control link and rod upwardly, said eyelet and ring will move upwardly to partially wrap the yarn around the cylinder to provide a line contact thereby increasing tension on the yarn.

5. A releasable yarn tension device for a hosiery knitting machine, said device comprising a horizontal bracket, a horizontal stud on said bracket, a friction cylinder of synthetic yieldable material removably fixed on said stud, an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said member being provided with a yarn receiving eyelet disposed on one side of said cylinder, spring means for urging said member upwardly toward a position with said eyelet disposed above said cylinder, a control link for holding said member down against the action of said spring means with said eyelet disposed substantially in alignment with the lowermost point on said cylinder, a yarn shifting rod slidably mounted on said bracket for substantially vertical movement, the lower end of said rod being connected to said control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantially in alignment with the lowermost point on said cylinder when in down position, whereby a strand of yarn drawn through said eyelet and ring will engage said cylinder in a substantially point contact to impart a minimum tension to the yarn and upon movement of said control link and rod upwardly, said eyelet and ring will move upwardly to partially wrap the yarn around said cylinder to provide a line contact thereby increasing tension on the yarn;

6. A releasable yarn tension device for a hosiery knitting machine, said device comprising a horizontal bracket, a horizontal stud on said bracket, a friction cylinder of synthetic yieldable material removably fixed on said stud, an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said member being provided with a yarn receiving eyelet disposed on one side of said cylinder, spring means for urging said member upwardly, a control link for holding said member down against the action of said spring means with said eyelet disposed substantially in alignment with the lowermost point on said cylinder, a yarn shifting rod slidably mounted on said bracket (for substantially vertical movement, the lower end of said rod being connected to said control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantially in alignment with the lowermost point on said cylinder when in down position, whereby a strand of yarn drawn through said eyelet and ring will engage said cylinder in a substantially point contact to impart a minimum tension to the yarn and upon movement of said control link and rod upwardly, said eyelet and ring will move upwardly to partially wrap the yarn around the cylinder to provide a line contact thereby increasing tension on the yarn.

7. A releasable yarn tension device for a hosiery knitting machine, said device comprising a horizontal bracket, a horizontal stud on said bracket, a friction cylinder of synthetic yieldable material removably fixed on said stud, an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said member being provided with a yarn receiving eyelet disposed on one side of said cylinder, spring means for urging said member upwardly, a control link for holding said member down against the action of said spring means with said eyelet disposed substantially in alignment with the lowermost point on said cylinder, a yarn shifting rod slidably mounted on said bracket for substantially vertical movement, said rod being connected to said control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantially in alignment with the lowermost point on said cylinder when in down position, whereby a strand of yarn drawn through said eyelet and ring will engage said cylinder in a substantially point contact to impart a minimum tension to the yarn and upon movement of said control link and rod upwardly, said eyelet and ring will move upwardly to partially wrap the yarn around the cylinder to provide a line contact thereby increasing tension on the yarn.

8. A releasable yarn tension device for a hosiery knitting machine, said device comprising a horizontal bracket, a horizontal stud on said bracket, a friction cylinder of yieldable material removably fixed on said stud, an elongated yarn takeup member pivotally mounted at one end on said bracket, the opposite end of said member being provided with a yarn receiving eyelet disposed on one side of said cylinder, spring means for urging said member upwardly, a control link for holding said member down against the action of said spring means with said eyelet disposed substantially in alignment with the lowermost point on said cylinder, a yarn shifting rod slidably mounted on said bracket for substantially vertical movement, said rod being connected to said control link and a yarn receiving ring on the upper end of said rod disposed on the opposite side of said cylinder from said eyelet and disposed substantially in alignment with the lowermost point on said cylinder when in down position, whereby a strand of yarn drawn through said eyelet and ring will engage said cylinder in a substantially point contact to impart a minimum tension to the yarn and upon movement of said control link and rod upwardly, said eyelet and ring will move upwardly to partially wrap the yarn around the cylinder to provide a line contact thereby increasing tension on the yarn.

References Cited in the file of this patent UNITED STATES PATENTS 387,251 ONeil Aug. 7, 1888 2,441,118 Boucrant May 4, 1948 FOREIGN PATENTS 523,580 Great Britain July 17, 1940 597,891 France Sept. 12, 1925