US2910850A

US2910850A - Yarn control means for textile machines

Info

Publication number: US2910850A
Application number: US551877A
Authority: US
Inventors: Held Joseph; Frank P Trumpio
Original assignee: Textile Machine Works
Current assignee: Textile Machine Works
Priority date: 1955-12-08
Filing date: 1955-12-08
Publication date: 1959-11-03
Anticipated expiration: 1976-11-03

Description

Nov. 3, 1959 .1. HELD ETAL 2,910,850

YARN CONTROL MEANS FOR TEXTILE MACHINES Filed Dec. 8, 1955 9 Sheets-Sheet l L. 5 INVENTORS.

Joseph Held y Fran Bfrzmz i0 M061 ATTORNEY.

Nov. 3, 1959 J. HELD ETAL 5 YARN CONTROL MEANS FOR TEXTILE MACHINES Filed Dec. 8. 1955 9 Sheets-Sheet 2 w rrrrrrrrrrrrrrrrrr mi 9g /67 4a r l Q 2 I I I57 265 i 292 i J INVENTORS.

Josqpk Held 6 Y Fran 1? fl'zm vio A TTORNE Y.

Nov. 3, 1959 J. HELD ET AL 2,910,850

YARN CONTROL MEANS FOR TEXTILE MACHINES Filed Dec. a. 1955 9 Sheets-Sheet 5 ATTORNEY.

Nov. 3, 1959 J. HELD ET AL 2,910,850

YARN CONTROL MEANS FOR TEXTILE MACHINES Filed Dec. 8. 1955 9 Sheets-Sheet 4 I N V EN TOR-5- Jaseph fie/ d 6 y FPa/M; R fill/2221050 ATTORNEY.

J. HELD ET AL YARN CONTROL MEANS FOR TEXTILE MACHINES 9 Sheets-Sheet 5 Nov. 3, 1959 Filed Dec. 8, 1955 Nov. 3, 1959 J. HELD ET AL 2,910,850

YARN CONTROL MEANS FOR TEXTILE MACHINES Filed Dec. 8, 1955 9 Sheets-Sheet 6 F1E- E /9/ IN V EN TOR-S.

J0.5'e k Held BY Fran P. Era/m nia ATTORNEY.

Nov. 3, 1959 J. HELD ET AL 2,910,850

YARN CONTROL MEANS FOR TEXTILE MACHINES Filed Dec. 8, 1955 9 Sheets-Sheet '7 o IL .1 E- ll Z72 f l O 275 O t, 2

250 //2 H \il 4 M221? f I! M6 1425 m0 92 h 0 /27 lg! 6 Z6 /22 a 00 J a7 9/ /z/ /47 /47 P 1 2--1. Li

WW4, QI

' I mo u 5 w av d- IN V EN TORS Joseph Held 4% ATTORNEY.

Nov. 3, 1959 J. HELD ET AL YARN CONTROL MEANS FOR TEXTILE MACHINES 9 SheetsSheet 8 Filed Dec. 8. 1955 al A FLE- "1 .5.-

INVENTORS.

Josqukfleld 6 y Emu n67]? Tram ATTORNEY.

Nov. 3, 1959 J. HELD ET AL 2,910,350

YARN CONTROL MEANS FOR TEXTILE MACHINES Filed Dec. 8. 1955 9 Sheets-Sheet 9 zoo FIE-.15.

F1 Ira--15- INVENTORS.

y EmmfR Zrzmioib ATTORNEY.

Uniteci States Patent YARN CONTROL MEANS FOR TEXTILE MACHINES Joseph Held, West Lawn, and Frank P. Trumpio, Temple, Pa., assignors to Textile Machine Works, Wyomissing, Pa., a corporation of Pennsylvania Application December 8, 1955, Serial No. 551,877

8 Claims. (CI. 66-86) This invention relates to yarn let-01f mechanisms for high speed warp knitting and like textile machines and more particularly to means for controlling the rotation of yarn beams of such machines to let off yarns at constant linear speeds as the yarns are withdrawn from the beams and formed into knitted loops by the fabricating means of the machines.

Heretofore, in wrap knitting and like machines operating at low fabricating speeds and employing a plurality or sheet of yarns, the yarns were carried on and withdrawn from beams by the combined action of the tensioning means for the yarns and the means for fabricating the yarns into fabric. Inasmuch as the beams normally turn easily on their bearings and if unrestrained would tend to overfeed under the pull of the yarns as :they are taken by the knitting instrumentalities, the rotation of the beams was conventionally controlled to provide a uniform movement of the yarns under the desired tension by friction braking devices acting on the beams or the mounting means therefore. However, on the more recent machines, such as high speed tricot machines, such brak- I ing devices have proved to be unreliable and incapable of providing a uniform feeding of the yarn at the desired tension resulting in uneven loop formation and fabrics of inferior quality. In efforts to improve the quality of the fabric numerous attempts were made to positively control the rotation of the beams to ensure that the yarns would be withdrawn from the beams at a constant speed by the fabricating means, such positive controls requiring means for compensating for the diminishing diameter of the windings of yarn on the beams.

In one form of such means the tension rod for the yarns was utilized to vary the rotative speed of the beams. In this device, the gradual increase in tension in the yarn resulting from the decrease in diameter of the winding of the yarns on the beams gradually displaced the tension rod to a point at which it was effective to operate means to correct the rotative speed of the beams. Other devices utilized the diameter of the windings and the peripheral speeds of the yarns on the beams as the control to cause the necessary adjustments in the rotation of the beams. However, while all of the prior arrangements were designed to produce a constant withdrawal of yarns from the beams by the fabricating means of the machine, the construction and operation of these devices caused the adjustments to the let-off speed of the beams to occur at stepped intervals which in turn caused the formation of definite patterns of loop length variation and resulted in the production of fabric of inferior quality or had other faults which prevented them from producing the desired results.

It is therefore an object of the invention to provide means to overcome the above mentioned and other difficulties occur ing in high speed fabricating machines employing a plurality or sheet of yarns.

Another object of the invention is the provision of improved means in a high speed warp or tricot knitting machine for positively controlling the rotation of the 2,910,850 Patented Nov. 3, 1959 yarn beams to let olf the yarns as they are withdrawn from the beams and knitted into fabric by the needles of the machine.

A further object of the invention is to provide means in a warp or tricot knitting machine for positively controlling the rotation of the yarn beams to let off the yarns, which means acts to vary the speed of rotation of the beams to maintain a uniform linear speed of the yarns let off the beams.

A still further object of the invention is to provide control means in a tiicot knitting machine for varying the speed of rotation of the yarn beams in relation to the linear speed of the yarns let off the beams, which control means is operated by the sheet of yarns as the yarns are withdrawn from the beams by the fabricating means of the machine.

Still another object of the invention is to provide means in a tricot knitting machine which is operated by the sheet of yarns as the yarns are withdrawn from the beams by the fabricating means of the machine to continuously adjust the speed of rotation of the beams to maintain the flow of yarns from the beams constant.

With these and other objects in view which will become apparent from the following detailed description of the illustrative embodiment of the invention shown in the accompanying drawings, the invention resides in the novel elements, features of construction and cooperation of parts, as hereinafter more particularly pointed out in the claims.

In the drawings:

Figure 1 is an end elevational view of a warp knitting machine having warp beam let-ofi mechanism, according to the invention, applied thereto;

Fig. 2 is an elevational view taken in the direction of the arrows 2-2 on Fig. 1, parts being shown .in cross section;

Fig. 3 is a cross-sectional view taken substantially along the line 3-3 of Fig. 2;

Fig. 4 is a view taken in the direction .of the arrows 44 of Fig. 2, certain parts being shown .in cross section;

Fig. 5 is a view on :an enlarged scale similar to a portion of Fig. 2 of a let-off control unit for one of the warp beams;

Fig. 6 is a view of the mechanism taken from the right of Fig. 5;

Fig. 7 is across-sectional View on an enlarged scale taken substantially along the line 7-7 of Fig. 5.;

Fig. 8 is across-sectional view takensubstantially along the .line 8-8 of Fig. 5 and shown enlarged relative to Fig. 5;

Fig. 9 is a cross-sectional view on a slightly enlarged scale taken substantially along the line 9-9 of Fig. 6;

Fig. 10 is a cross-sectional view on an enlarged scale taken substantially along the line 1010 of Fig. 6;

Fig. 1.1 is a cross-sectional view on an enlarged scale taken substantially along the line 11-11 of Fig. 6 with parts being omitted and other parts being broken away to more clearly show details in the background;

Fig. 12 is a view on an enlarged scale taken substantially along the line 12--12 of Fig. 5, parts being shown in elevation and others shown in cross section;

Fig. 13 is a cross-sectional view taken substantially along the line 13-43 of Fig. 5, and shown enlarged with respect to Fig. 5;

Fig. 1 4 is a cross-sectional view on an enlarged scale taken substantially along the line 14-14 of Fig. 5, distance breaks being shown to indicate the omissions of parts;

Fig. 15 is .a cross-sectional view on an enlarged scale taken substantially along the line 151 5 of Fig. 8;

Fig. 16 is a detailed cross-sectional yiew on an en- 3 larged scale taken substantially along the line 16-16 of Fig. 6;

Fig. 17 is a detailed cross-sectional view taken substantially along the line \17--17 of Fig. 6 and shown enlarged relative to Fig. 6;

I Fig. 18 is a detailed cross-sectional view on an enlarged scale taken substantially on the line 18-18 of Fig. 6;

Fig. 19 is a cross-sectional view on an enlarged scale taken along the line 1919 of Fig. and

Fig. 20 is a cross-sectional view on an enlarged scale taken along the line 20-20 of Fig. 10.

V In warp or tricot knitting machines as the loop forming mechanism is operated it creates a pull in the yarns, carried by the warp beams, suflicient to readily rotate the beams in their bearings so that the yarns themselves normally serve as the power or drive means for rotating the beams. The mechanism now to be described serves to control this turning movement or let-off of the beams under the pull of the yarns. However, inasmuch as the control mechanism is in driven relationship to a power shaft of the machine, it would, if the machine was running, but for one reason or another no or little yarn was being taken by the needles, serve to rotate the beams.

The mechanism shown in the drawings comprises a control unit having a constant speed input shaft, a yarn beam shaft and means intermediate the shafts which is automatically adjustable to regulate the speed of the yarn beam shaft. The control unit is shown applied to a high speed warp or tricot knitting machine for controlling each of the yarn beams to let off the yarn from the beams at a constant linear speed as it is knitted into fabric by the knitting elements of the machine; More specifically the beams are permitted to rotate at varying speeds by the control units to compensate for the varying diameter of the sheets of yarns on the beams and thereby maintain the yarns at constant linear speeds as they are fed to the knitting elements of the machine.

Referringto Figs. 1 to 4, inclusive, there is shown a portion of a framework 26 of a high speed warp or tricot knitting machine including a base member 28 and end frames, one of which is shown at 29, which supports the fabric forming mechanisms of the machine including needle bar 27 carrying spring bearded needles 33, a presser member 30 for closing the beards of said needles, a sinker bar 31 carrying sinkers 34, and front and rear yarn guide bars '32 carrying yarn :guides 44 for yarns B5. The needle bar 27 carrying needles 33, presser member 30 and the sinker bar 31 carrying sinkers 34 are operated in a suitable or usual manner by means (not shown) to form the yarns 35, fed to the needles by the guides 44, into loops of a fabric. The yarns 35 for the front and rear groups of guides 44 follow separate upper and lower paths, respectively, and are withdrawn from upper and lower supply beams 36, respectively, as shown in Fig. 3 each of which is carried by stub shafts 38, the ends of which are rotatably mounted in ball bearlugs 39 carried in the end frames 29 of the machine, the right end mounting for one of the stub shafts being shown in Figs. 2 and 9. The structure and mounting of the beams 36 form no part of the instant invention but It is to be understood that the beams are of the usual sectional type which may be readily removed from the stub shafts 38, when the yarn supply is exhausted, and replaced by beams having a fresh supply of yarns.

From the upper beam 36 the yarns 35 are guided over a control roller or runner 37 secured to a shaft 43 which 1s rotatably mounted in the framework 26. The roller 37 1s suitably covered with rubber or other material which will provide good frictional engagement With the yarn and prevent slippage of the yarn on the surface of the roller. From the'roller 37 the yarns 35 pass beneath a guide roller 40, also rotatably mounted in the framework 26, through a comb device .41 carried on the framework and over a rod 42, forming: part of a tension device 45, to the front yarn guides 44. The tension device 45 which may be of any suitable type maintains a constant tension on the yarns 35 between the needles 33 and the beam 36 and holds the yarns tightly against the roller 37 to thereby ensure that the roller is turned at a surface speed equal to the travel of the yarns as and for the purpose hereinafter set forth. The yarns 35 from the lower beam 36 are guided along a path similar to the path followed by the yarns from the upper beam 36 over a roller or runner 48, beneath a guide roller 49, through a comb device 53 and over a tension rod 54.

In forming knitted fabric on tricot knitting machines it is desirable to predetermine the length of the fabric loops and then to maintain such length of loops constant throughout the fabric. In order to do this it is essential that the needles 33 withdraw the yarns 35 from the beams 36 at the predetermined rate to thereby prevent fluctuations in tension on the yarns, which tend to change the length of the loops in the completed fabric. For this purpose, the rotation of each of the beams 36 is positively controlled by a power driven unit indicated generally at 46 (Figs. 1 and 2) both of which units are identical and only one of which will be described hereinafter.

The unit 46 is carried in a housing 47 secured by bolts St to a bracket 51 which is in turn secured to the right end frame 29 by bolts 52 (Figs. 5 and 9). As shown in Fig. 9, the right end of the stub shaft 38 for the beam 36 extends through the bracket '51 into the housing 47 and has a reduced end portion 55 on which is mounted a Worm gear 56 (Fig. 8). A key 57 prevents the worm gear '56 from turning on the end portion 55 and the worm gear is held against axial movement by a washer 59 and a bolt 60 Which is threaded in the reduced end portion of the stub shaft. The worm gear 56 meshes with a worm 61 secured on a shaft 62 which is mounted for rotation in ballbearings 65 or the like carried in the walls of the housing 47 as shown in Fig. 13. A worm gear 66, rotatably carried on the shaft 62 in abutting engagement with an enlarged portion 67 of the shaft, has one or more projecting teeth 70 engaging in corresponding notches 711 in one face of a disc 72 (Fig. 8) also rotatably is provided with radially extending V-shaped notches mounted on the shaft 62. The other face of the disc 72 is provided with radially extending V-shaped notches 75 which are adapted to be engaged by spring pressed detents 76 carried in a collar 77 secured to the shaft 62 (Figs. 8, l3 and 15). The worm gear 66 is in meshing engagement with a worm 80 which is formed as an integral part of a stub shaft 81 mounted for rotation in ball bearings 82 carried in the housing 47 as shown in Fig. 11. During normal operation, the rotation of the worm gear 66 is controlled by the worm 80 and the engagement of the detents 7 6 in the notches 75 provide the driving connection between the worm gear and shaft 62. The detents '76 will, however, yield to permit the shaft 62 to be manually rotated relative to the worm gear 66 by a hand wheel 85 secured to the shaft when it is desired to manually turn the beam 36 when the machine is idle.

The shaft 81 has a flange 86 fixed to the inner end thereof, the flange having a friction disc 87, preferably of a non-metallic material such as nylon or the like, secured thereto by a plate 90 and bolts 91 (Fig. 11). The friction disc87 is adapted to be engaged by a member 92 for rotation therewith. Member 92 is in the form of a half sphere and is rotatably mounted by means of roller or pin bearings 95 on a stud 96. The stud 96 extends through a support member 97 and is secured thereto by a nut 101'). The member 92 is positioned on the stud 96 between an enlarged head portion 101 of the stud and a thrust bearing 102 mounted on member 92 and abutting the underside of the support member 97 (Fig. 11). The support member 97 is provided with opposed bearing portions 105 the right one of .WhiQh fixedly carries one end of a pin 1'06 and the left bearing portion of which fixedly carries a pin 107 (Fig. 12), the pins being axially aligned with respect to each other. The

pins

106 and 107 extend through and are pivotally supported'in arms 110 of a yoke member 111 which is guided for vertical movement on a pin 112 suspended from a bearing member 115 extending through and secured to the housing 47 by bolts 114 (Figs. 11 and 12). The yoke member 111 has an upper flat parallel sided portion 116 which interfit's' a slot 117 in the bearing member 115 to prevent rotation of the yoke member.

Axially aligned with the shaft 81 and friction disc 87 is a second friction disc 120 of the same material as disc 87 which is adapted to engage the member 92 at a point opposite to the disc 87. The disc 120 is carried on and secured to a flange 121 for rotation therewith by means of a plate 122 and bolts 125, as shown in Fig. 11. The flange 121 is secured to the inner end of a stub shaft 126 which is mounted for rotation in ball bearings 127 carried in a part of the housing 47 (Fig. 11). The flange 121 has a toothed gear portion 130 which is in meshing engagement with a gear 131 secured to a shaft 132 mounted for rotation in bearings 135 carried in the housing 47 (Figs. 7 and 9). The shaft 132 has a pulley 136 secured thereto (Fig. 9) which is connected by a V belt 137 to a pulley 140 fixed on a main operating shaft 141 of the machine, as shown in Figs. 2 and 4.

The member 92 is normally biased toward the

friction discs

87 and 120 to maintain driving engagement between the member and discs. For this purpose the yoke member 111 carries pins 142 which extend outwardly from and at right angles to the axis of the member 92, and with the axis of the pins lying parallel to the axis of the

stub shafts

81 and 126. Each of the pins 142 has a bracket 145 secured thereto, the bracket supporting a pair of pins 146 each of which acts to anchor one end of a spring 147 (Figs. 7, 10 and 11). The other end of each spring 147 is anchored by arms of a lever 150 fixed on a shaft 151 pivotally mounted in a part of the housing 47 (Figs. 7 and 9).

ltwill be obvious from the drawings and foregoing description that the speed of rotation of stub shaft 126 is determined by the speed of rotation of the machine shaft 141 through the V-belt 137, gear 131 and gear portion 130, and that member 92 will in turn rotate with the friction disc 120. With the member 92 in the position of Fig. 11, its neutral position, the shaft 126 and disc 120 and the shaft 81 and disc 87 will rotate at a one-to-one ratio and the worm 80 on the shaft 81 in mesh with the worm gear 66, and the Worm 61 in mesh with worm gear 56 will provide for rotation of the beam at a proportionate speed determined by the ratio between the worms and worm gears. i I

In order to change the rotative speed of the beam 36, the member 92 must be rotated clockwise or counterclockwise about the axis of the

pins

106 and 107 as viewed in Fig. 11, to vary the rotative ratio between the discs s7 and 120 as will hereinafter be fully explained. For this purpose a lever 152 is secured to a reduced end portion 155 of the pin 107, the lever having arms 156 which straddle a nut 157 carried on a threaded portion 160 of a shaft 161 (Figs. 10 and 12) mounted for rotation in the housing 47. As viewed in Fig. 10 each arm 156 of the lever 152 is slotted at 162 to receive a dog 165 formed on and projecting from opposite sides of the nut 157.

The shaft 161 is adapted to be rotated both manually and automatically in opposite directions to move the lever 152 and member 92 in either a clockwise or counterclockwise direction to adjust the position of themer'nber 92 in relation to the discs 87 and 129. For manually rotating the shaft 161, the right end of the shaft carries a sleeve 166 which is slidable axially of the shaft. The outer end of the sleeve 166 has secured thereto a handwheel 167 which is provided with keyways 170 for sliding engagement by key portions 171 formed on and projecting from a collar 172 secured to the end of the shaft 161, as shown in Figs. 18 and 19. The left end of the sleeve 166 is provi-de'd with a pair of projecting teeth 175 for engagement with a pair of slots 176 formed: in a hub portion 177 of a sprocket wheel 180 mounted on the shaft 161 between the left end of the sleeve and a collar 181 secured to the shaft (Figs. 18 and 20). A spring 182 surrounding the shaft 161 between the right end of the sleeve 166 and the collar 172 normally biases the sleeve 166 toward the left (Fig. 18) to engage theteeth 175 in one of the slots 176 in the sprocket wheel 180.

The sprocket wheel. 180 is connected by a chain 185 to a sprocket wheel 186 secured to a hub portion 187 of a yoke member 190 forming part of a speed differential 189. The yoke member 190 is rotatably mounted on a shaft 191 between a collar 192 and a bevel gear 195 both of which are secured to the shaft (Figs. 7, l0 and 17). The shaft 191 is mounted for rotation in ball bearings 196 carried in the housing 47. The yoke member 190 has arms 197 each of which has fixed therein a stud 206 for rotatably supporting a bevel gear 201 for meshing engagement with the bevel gear 195. A second bevel gear 206 is mounted on shaft 121 in axially spaced relationship to gear 195 by a sleeve 202 and a collar 205 fixed to the shaft. Gear 206 is freely rotatable on the shaft and has meshing engagement with the bevel gears 201. The bevel gear 206 has a worm gear portion 207 having meshing engagement with a worm 210 secured to a shaft 211 which is rotatably mounted in ball bearings 212 carried in the housing 47 (Figs. 8 and 13). A sprocket wheel 215 secured to the end of the shaft 191 is connected by a chain 216 to a sprocket wheel 217 secured to the end of the shaft 43 (Figs. 2', 4 and 16') for the runner 37.

The shaft 211 carries a second worm gear 220 which meshes with a worm 221 carried by a stub shaft 22 which is similar in structure to and mounted for rotation in the housing 47 in the same manner as stub shaft 81 as hereinbefore set forth. The shaft 222 has a flange 225 secured thereto on which is mounted a friction disc 226, the friction disc being held on the flange by a plate 227 and bolts 230. The friction disc 226 is adapted to engage a memher 231 which is in the form of a half sphere and identical in structure to the member 92. The member 231 is rotatably mounted on a stud 228 and pivotally mounted in a yoke member 229 by means of

pins

233 and 234 and the yoke member is guided for vertical movement on a pin 223 and held against rotation, in the same manner as member 92, by parts of like structure not specifically referred to herein.

AXially aligned with the stub shaft 222 and friction disc 226 is a second friction disc 232 adapted to engage the member 231 at a point opposite to the friction disc 226 (Fig. 9). The friction disc 232 is carried on and secured to a flange 235 for rotation therewith by a plate 236 and bolts 237. The flange 235 is secured to a stub shaft 240 which is mounted for rotation in the housing 47 in the same manner as stub shaft 126. The flange 235 has a toothed gear portion 241 which meshes with and is driven by the gear 131. The yoke member 229 for the member 231 is provided with springs 238 to bias the member 231 into engagement with the

friction discs

226 and 232.

For pivotally adjusting the member 231 to vary the driving relation between the

friction discs

226 and 232, a lever 242 is secured to the reduced end portion 239 of the pin 234, the lever having arms 245 straddling a nut 246 similar to the nut 157 and mounted on a threaded portion 247 of a shaft 250 which is mounted for rotation in the housing 47 (Figs. 11 and 12). The arms 245 are slotted at 251 to receive dogs 252 formed on and extending from opposite sides of the nut 246. A hand wheel 255 is secured to the right end of the shaft 250 whereby the shaft may be manually adjusted for the purpose to be hereinafter set forth.

The

members

92 and 231 are adapted to be moved vertically on the

pins

112 and 223, respectively, from the positions shown in the figures to disengaged position with respect to the

friction discs

87, 120 and 226, 232 respectively when manual adjustments are to be made to the

shafts

161 and 250 when the machine is idle. For vertically moving the member 92, the pin 106 pivotally carries one end of a link 256 and the pin 107 carries one end of a link 257, the links being pivotally connected to studs 260 secured in the free ends of levers 261, as shown in Figs. 9, 10 and 12. For vertically moving the member 231, the pin 233 pivotally carries one end of a link 258 and the pin 234 pivotally carries one end of a link 259, the links being pivotally connected to studs 263 secured in the free ends of levers 264. The levers 261 and 264 t are secured to a shaft 262 which is mounted in the walls of the housing 47, the left end of the shaft extending through a wall of the housing (Fig. 12) and carrying a hand lever 265 by means of which the shaft is turned to move the

levers

261 and 264 counterclockwise and the

links

256, 257 and 258, 259 clockwise to raise the yoke members 111 and 229 and

members

92 and 231, respectively. These movements of the levers and links are only suflicient to permit the levers to be adjusted in a counterclockwise direction as viewed in Fig. 10 from a position at the right side of the vertical center line passing through the shaft 262 and the members 92 and 231 (Fig. 10) to a position at the left side of said center line, the levers and links being yieldably maintained in the latter position by the

springs

147 and 238. In order to limit the counterclockwise movement of the shaft 262, so that the

members

92 and 231 will not contact their respective discs, the shaft carries a collar 266 having a pin 267 for engagement with the head of a screw 270 (Fig. 16) carried in the housing 47.

The shaft 250 has a worm 271 fixed thereon for meshing engagement with a worm gear 272 secured to a shaft 275 having its right end mounted for rotation in the housing 47, as shown in Fig. 14. The left end of the shaft 275 is rotatably mounted in a sleeve 276 which is in turn rotatably mounted in the opposite wall of the housing 47. The shaft 275 extends beyond the end of the sleeve 276 and carries a dial 277 (Figs. 6 and 14) for turning movement therewith, the dial being provided with micrometer markings as indicated in Fig. 5. A pointer member 280 secured to the housing 47 cooperates with the markings to indicate the speed setting of the roller 37 (Figs. 5 and 6). The sleeve 276 has a worm gear portion 281 which is in meshing engagement with a worm 282 secured to the shaft 161. The sleeve 276 carries a dial 285 at its outer end having markings with Which the pointer 280 cooperates to indicate the speed at which the beam 36 is rotating to let off the required amount of yarn.

In operation, shaft 132 (Figs. 4 and 9) is driven at a speed proportional to the speed of the machine from the main drive shaft 141 through the medium of

pulleys

140 and 136 and belt 137. If the speed of the machine is maintained constant the speed of shaft 132 will similarly be maintained constant and in any event the relative speeds of the two will remain the same. Hence shaft 132 is referred to as a constant speed input shaft. Shaft 132 through

gears

131, 130 and 241 in turn drives

friction discs

120 and 232, respectively.

The position of member 231 relative to the

friction discs

226 and 232 is initially adjusted by the handwheel 255 so that disc 226 is driven at a speed bearing a required fixed relationship to the desired linear speed of the yarn let off from the beams, and worm 221, the shaft 211, worm 210, worm gear 207 and bevel gear 206 on the shaft 191 similarly rotate at a constant rate having a fixed relationship to the desired linear speed of the yarn. As the yarns 35 are drawn off the beam 36 and formed into loops by the needles 33 the yarns passing over the runner 37 causes it to rotate at a surface speed equal to the linear speed of the yarn and in turn drive the chain 216 to rotate the shaft 191 and the bevel gear 195 which is secured to the shaft. When the shaft 191 and bevel gear 195 are rotating at the same speed as bevel gear 206 and worm gear 207, member 92 is positioned relative to the friction discs 87 and to permit rotation of the worm gear 56 and beam 36 to let off the yarns 35 at the said linear speed.

As the needles 33 continue to draw the yarn 35 from the beam 36 the diameter of the coils on the beam is gradually decreased which results in less yarn being delivered to the needles thereby causing the runner 37 to slow down and in turn causing the speed of the shaft 191 and bevel gear 195 to lag behind the bevel gear 206 and worm gear 207. This action immediately causes the bevel gears 201, meshing with the

bevel gears

195 and 206, to rotate in a manner to turn the yoke member 190 relative to the shaft 191. Rotation of the yoke member 190 is transmitted through the chain to turn the shaft 161 to adjust the position of the member 92 relative to the

friction discs

87 and 120 to thereby increase the speed of rotation of the beam 36. When the linear speed of yarns drawn by the needles reaches the desired predetermined rate, the runner 37 will again be rotating at the desired linear speed of the yarns and hence will rotate the shaft 191 and the bevel gear 195 at the same speed as the bevel gear 206 and the bevel gears 201 will be rotated without turning the yoke member 190. In view of the fact that only a slight change in the linear speed of the yarns passing over the runner 37 is required to cause the differential 189 to adjust the member 92 relative to the

friction discs

87 and 120, the continuous decrease in the length of the yarn coiled on the beam will also result in the continuous adjustment of the member 92 to increase the speed of rotation of the beam to maintain the desired constant linear flow of yarns withdrawn from the beam by the needles.

When the supply of yarns 35 on the beam 36 is exhausted and the empty beam replaced by a full one, the speed of the beam must be decreased to the point at which the linear speed of the yarns let off the beam causes the runner 37 to rotate the shaft 191 and bevel gear 195 at the same speed as the bevel gear 206. This decrease in the rotational speed of the beam may be automatically effected by the runner 37 which will be operated by the yarns to rotate the bevel gear 195 faster than the bevel gear 206 thereby resulting in a rotation of the yoke member to turn the shaft 161 and adjust the member 92 until the speed of the bevel gears is again equal. However, inasmuch as the needles 33 are forming loops of greater length than desired during this automatic adjustment of the speed of the beam 36 and considerable fabric will be knitted during this period it is the better practise to manually rotate the shaft 161 to adjust the member 92 to its approximate position when the diameter of the coils of yarns on the beam is the greatest, which may be determined by a previously noted point on the dial 285. This may be accomplished without affecting the position of the yoke member 190 by manually shifting the handwheel 167 and the sleeve 166, which is secured to the handwheel by a set screw 168 (Fig. 19), toward the right, as viewed in Fig. 18, against the action of spring 182 to disengage the teeth 175 from the slots 176 in the sprocket wheel 180 and then rotating the shaft 161. The manual adjustments may be made while the machine is operating, or by manually disengaging the

members

92 and 231 from their respective friction discs, as hereinbefore set forth, the adjustments may be made when the machine is idle. From this approximate manual setting of the member 92 the runner 37 then will automatically operate to equalize the speeds of the bevel gears and 206, as hereinbefore set forth with a minimum production of defective fabric.

The lower unit 46 for controlling the rotation of the in structure and operation to the unit 46 controlling the rotationof the upper beam as hereinbefore set forth. The shaft 132 of the lower unit 46 is provided with a pulley 286 which is connected by a V belt 287 to a pulley 290 fixed on the main operating shaft 141 of the machine adjacent to the pulley 140 (Figs. 2 and 4). The shaft 191 of the lower unit 46 carries a sprocket wheel 291, similar to the sprocket wheel 215 of the upper unit 46, the sprocket wheel being connected by a chain 292 to a sprocket wheel 295 secured to the end of a shaft 296 to which therolle'r 48 is secured.

It will be understood that the improvements specifically shown and described, by which the above described results are obtained, can be changed and modified in various ways withoutdeparting from the invention herein disclosed and hereinafter claimed.

We claim: I c

1. In a tricot knitting machine having means for supplying a'sheet of yarns to fabricating means of the machine, comprising a beam for said sheet of yarns and means for positively controlling the rotation of said beam to let off said yarns, said positive control means including a driven shaft, variable speed means connecting said driven shaft to said beam, a rotatable member, adjustable variable speed means connecting said driven shaft and said rotatable member, a roller member engaged by said sheet of yarns and driven by the movement of said yarn from said beam to said fabricating means, tensioning means for said sheet of yarns adapted to maintain said yarns in driving engagement with said roller membet, and means operative, to adjust said first mentioned variable speed means in response to variations in the rotative speeds of said rotatable member and said roller member.

2. In a tricot knitting machine having a beam to support a sheet of yarns coiled thereon, means for withdrawing said sheet of yarns from said beam and for fabricating said yarns into fabric, and means for controlling the rotation of said beam to let-off said yarns at a linear speed corresponding substantially to a predetermined uniform linear speed, said controlling means comprising a driven shaft, variable speed means operatively connecting said driven shaft to said beam including a friction disc rotated with said driven shaft, a second friction disc operatively connected to said beam, an adjustable driving member interposed between said friction discs, and means for adjusting the position of said driving member relative to said friction discs, a rotatable member, a second variable speed means connecting said driven shaft and said rotatable member and being adjustable to drive said rotatable member at a constant speed corresponding to said predetermined uniform linear speed of said yarns, a roller member engaged by said sheet of yarns and driven by the movement of said yarns from said beam to said fabricating means, tensioning means for said sheet of yarns adapted to maintain said yarns in driving engagement with said roller member, differential means operatively connecting said rotatable member and said roller member, and means operatively connecting said differential means and said adjusting means for said first mentioned variable speed means.

3. In a tricot knitting machine having a'beam to support a sheet of yarns coiled thereon, means for withdrawing said sheet of yarns from said beam and for fabricating said yarns into fabric, and means for controlling the rotation of said beam to let off said yarns at a linear speed corresponding substantially to a predetermined uniform linear speed, said controlling means comprising, a driven shaft, variable speed means connecting said driven shaft to said beam, means for adjusting said variable speed means, a rotatable member, a second variable speed means connecting said driven shaft to said rotatable member and being adjustable to drive said rotatable member at a constant speed proportional to said predetermined uniform linear speed of said yarns, a roller member engaged by said sheet of yarns and driven by the movement of said yarns from said beam to said fabricating means, tensioning means for said sheet of yarns adapted to maintain said yarns in driving engagement with said roller member, differential means operatively connecting said rotatable member and said roller member, and means operatively connecting said differential means to the adjusting means for said first mentioned variable speed means. p i

4. In a tricot knitting machine having a beam to su port a sheet of yarns coiled thereon, means for withdrawing said sheet of yarns from said beam and for fabricating said yarns into fabric, and means for controlling the rotation of said beam to let off said yarns at a linear speed corresponding substantially to a predetermined uniform linear speed, said controlling means comprising, a shaft driven at a constant speed, variable speed driving means operatively connecting said driven shaft to said beam, a rotatable member, a second variable speed drive means operatively connecting said driven shaft and said rotatable member, means for adjusting said second variable speed drive means for rotating said ro tatable member at a speed proportional to said predetermined uniform linear speed of said yarns, and means for adjusting said first mentioned variable speed driving means including a roller member engaged by said sheet of yarns and driven by the movement of said yarns from said beam to said fabricating means, tensioning means for said sheet of yarns adapted to maintain said yarns in driving engagement with said roller member, differential means operatively connecting said rotatable member and said roller member, and means operatively connecting said differential means and said adjusting means for said first mentioned variable speed means.

5. In a tricot knitting machine having a beam to support a sheet of yarns thereon, means for withdrawing said sheet of yarns from said beam and for fabricating said yarns into fabric, and means for controlling the rotation of said beam to let off said yarns at a linear speed corresponding substantially to a predetermined uniform linear speed, said controlling means comprising, a driven shaft, variable speed means operatively connecting said driven shaft and said beam, means for adjusting said variable speed means, a rotatable member, a second variable speed means operatively connecting said driven shaft and said rotatable member including a friction disc rotatable by said driven shaft, a second friction disc connected to said rotatable member, a driving member interposed between said friction discs and means for adjusting the position of said driving member relative to said friction discs whereby said rotatable member may be set to rotate at a speed corresponding to said predetermined uniform linear speed of said yarns, a roller member engaged by said sheet of yarns and driven by the movement of said yarns from said beam to said fabricating means, differential means connecting said rotatable member and said roller member, and means connecting said differential means and said adjusting means for the first men tioned variable speed means.

6. In a tricot knitting machine having a beam to support yarns coiled thereon, means for withdrawing said yarns from said beam and for fabricating said yarns into fabric, and means for controlling the rotation of said beam to let off said yarns at a linear speed corresponding substantially to a predetermined uniform linear speed, said controlling means comprising, a driven shaft, variable speed means operatively connecting said driven shaft to said beam including a friction disc rotated with said driven shaft, a second friction disc operatively connected to said beam, an adjustable driving member interposed between said friction discs, and means for adjusting the position of said driving member relative to said friction discs, a rotatable member, a second variable speed means connecting said driven shaft and said rotatable member and being adjustable to drive said rotatable member at a constant speed corresponding to said predetermined uni- 11 form linear speed of said yarns, a roller member engaged and driven by said yarns during rotation of said beam to .let off said yarns, differential means operatively connecting said rotatable member and said roller member, and means operatively connecting said differential means and said adjusting means for said first mentioned variable speed means.

7. In a tricot knitting machine having a beam to sup- :port yarns coiled thereon, means for withdrawing said yarns from said beam and for fabricating said yarns into fabric, and means for controlling the rotation of said beam to let off yarns at a linear speed corresponding substantially to a predetermined uniform linear speed, said controlling means comprising a driven shaft, variable speed means operatively connecting said driven shaft to said beam including a friction disc rotated with said driven shaft, a second friction disc operatively connected to said beam, an adjustable driving member interposed between said friction discs, and means for adjusting the position .of said driving member relative to said friction discs, a rotatable member, means connecting said driven shaft and said rotatable member to drive said rotatable member at a constant speed corresponding to said predetermined uniform linear speed of said yarns, a roller member engaged and driven by said yarns during rotation of said beam to let off said yarns, differential means operatively connecting said rotatable member and said roller member, and means operatively conecting said differential means and said adjusting means for said first mentioned variable speed means.

8. In a tricot knitting machine having a beam to support yarns coiled thereon, means for withdrawing said yarns from said beam and for fabricating said yarns into fabric, and means for controlling the rotation of said beam to let off said yarns at a linear speed corresponding to a predetermined uniform linear speed, said controlling means comprising, a driven shaft, variable speed means operatively connecting said driven shaft and said beam, means for adjusting said variable speed means, a rotatable member, a second variable speed means operatively connecting said driven shaft and said rotatable member including a friction disc rotatable by said driven shaft, a second friction disc connected to said rotatable member, a driving means interposed between said friction discs and means for adjusting the position of said driving member relative to said friction discs whereby said rotatable member may be set to rotate at a speed corresponding to said predetermined uniform linear speed of said yarns, a roller member engaged and driven by said yarns during rotation of said beam to let off yarns, differential means connecting said rotatable member and said roller member, and means connecting said differential means and said adjusting means for the first mentioned variable speed means.

References Cited in the file of this patent UNITED STATES PATENTS Winslow et al. June 17, 1958