US3089320A

US3089320A - Method of knitting

Info

Publication number: US3089320A
Application number: US248339A
Authority: US
Inventors: Paul L Thurston
Original assignee: Textile Machine Works
Current assignee: Textile Machine Works
Priority date: 1950-09-09
Filing date: 1951-09-26
Publication date: 1963-05-14
Anticipated expiration: 1980-05-14
Also published as: FR1055970A; DE884541C; GB717684A

Description

May 14,1963

Original Filed Sept. 9, 1950 P. L. THURSTON 3,089,320

METHOD OF KNITTING l5 Sheets-Sheet l 3maentor /M/L. TAM/774024 attorney May 14, 1963 P. THURSTON 3,089,320

METHOD OF KNITTING Original Filed Sept. 9. 1950 l5 Sheets-Sheet 2 I I l n Inventor Paw/ L. ThM/"ffflh (Ittorneg May 14,1963 P.IL. THURSTON 3,089,320

METHOD OF KNITTING v Original Filed Sept- 9, 1950 15 Sheets-Sheet;

3nventor (Ittorneg y 4, 1933 P. THURSTON 3,089,320

' METHOD OF KNITTING Original Fil ed Sept. 9, 1950 15 Sheets-Sheet 6 JV I Pau/ L. 7/7006)? (Ittorneg May 14, 1963 P. L. THURSTON METHOD OF KNITTING l5 Sheets-Sheet 7 Original Filed Sept. 9. 1950 3nventor /%u/ L. Thu/72% (Ittorneg 15 Sheets-Sheet 8 P. L. THURSTON METHOD OF KNITTING May 14, 1963 Original Filed Sept. 9, 1950 (Ittomeg May 14Q1963 I P. L. THURSTON 3,089,320

Original Filed Sept. 9, 1950 METHOD OF KNITTING l5 Sheets-Sheet 9 ill: 5 [1111; lull Zmventor /%M/ 4 7720/1772 attorney May 14, 1963 P. L. THURSTON METHOD OF KNITTING l5 Sheets-Sheet 10 Original Filed Sept. 9, 1950 Y Zinventor PQM/ A %z/rjf n (Ittorneg May 14, 1963 P. L. THURSTON METHOD OF KNITTING 15 Sheets-Sheet 11 Original Filed Sept 9, 1950 0 1 2 3 4 5 M mu 1. 1. 1 I. w. 4 a z w 1 1 w; I

9 7- 7 7 7- 5 M w 0 w M M m H 2- 2 2 Z 0 W h I 6 6 6 6 0 0 0 2 z m 2, Al. I I I I l Enventor Pam/ L, Thu/ 7% (Ittorneg May 14, 1963 P. THuRsTdN 3,089,320

METHOD OF KNITTING Original Filed Sept. 9, 1950 15 Sheets-Sheet 12 0000000000. GDUO...

nuqqpynnnnnno uununnnunnnun 3m entor Pou/ L Thu/157 017 May 14, 1963 P. L. THURSTON METHOD OF KNITTING Original Filed Sept. 9, 1950 15 Sheets-Sheet 13 1 1 I Q l I I I l l I I; I l I l I l I L T I I Zinnentor Pcw/ L, Thur f Cittorneg Y M, 1963 P. L. THURSTON 3,089,320

METHOD OF KNITTING Original Filed Sept. 9, 1950 15 Sheets-Sheet 14 Summer Pau/ L Thurfzan attorney May 14, 1963 P. L. THURSTON METHOD OF KNITTING Original. Filed Sept. 9, 1950 15 SheetsSheet 15 Qttorneg United States Patent 3,089,320 METHOD OF KNITTING Paul L. Thurston, Martinsburg, W. Va., assignor, by mesne assignments, to Textile Machine Works, Reading, Pa., a corporation of Pennsylvania Original application Sept. 9, 1950, Ser. No. 183,989. Di-

vided and this application Sept. 26, 1951, Ser. No. 248,339

8 Claims. (CI. 66-43) The present invention relates to knitting machines and, particularly, to circular knitting machines. It is especially applicable to machines for knitting circular seamless hosiery.

This application is a division of my application, Serial No. 183,989, filed September 9, 1950, now Patent No. 2,680,961.

' While many mechanisms have been proposed for producing different patterns in knitted fabrics, the patterning potentialities of such mechanisms have been limited. This is especially true with respect to solid color patterns, as distinguished from plating where the back yarn tends to show through. Moreover, with present machines, attempts to make more difiicult patterns result in decrease of the production of the machines to a point where they are uneconomical to operate. In some instances, hand operations are necessary. The problem of patterning is still more difiicult in small diameter machines such as those used for producing hosiery by reason of space limitations. In automatic hosiery machines, the difficulty is increased by the necessity of operating by reciprocation and widening and narrowing to produce heel and toe pockets.

It is an object of the present invention to provide a knitting machine with far greater patterning capabilities than the knitting machines presently available. These patterning capabilities can be used either to produce decorative designs or to produce different fabric structures. A further object of the invention is to provide a machine that is wholly automatic in its operation and produces diflicult patterns while maintaining a high rate of production. While the invention is applicable to knitting machines for many diiferent types of fabric, it is especially advantageous in small diameter circular knitting machines for automatically producing seamless hosiery and, for this reason, a machine of this type is illustrated in the drawings. It will he understood, however, that this machine is shown and described merely by way of example and that the invention is in no way limited to it. As will be seen from the description and drawings, the machine in accordance with the invention is basically different from knitting machines heretofore available and embodies many novel features. While it is preferable to use all of these features to gain full advantage of the invention, it will be understood that certain features can be used without using others.

In accordance with the invention, the needles of the knitting machine are individually operated and their operation is electrically controlled, needle selection being effected by means of electrical control circuits rather than by conventional cams, jacks, etc. The control circuits provide both patterning selection and sequence selection. Patterning selection determines which needles operate and how they operate. Sequence selection determines the timing and sequence of operation of the selected needles.

In the preferred embodiment of the invention, each needle is individually controlled in each course. The electrical operation of the needles offers many possibilities, such as cross-connecting or interconnecting certain needles electrically by means of switching, and also the possibility of switching from one selection or sequence control to another. Preferably, the yarn selection is also controlled electrically to provide wide selection and extremely flexible control. Many other novel features and advantages of the invention will appear from the following description in conjunction with the accompanying drawings, in which:

' FIG. 1 is a front elevation of a machine embodying the present invention.

FIG. 2 is a left side elevation of the machine.

FIG. 3 is a right side elevation.

FIG. 4 is a fragmentary view corresponding to a portion of FIG. 3 but with certain parts removed in order to show other parts behind them.

' FIG. 5 is a plan view of the machine with certain of the superstructure cut away.

FIG. 6 is a schematic perspective view showing connections for raising the yarn-feeding head of the machine.

FIG. 7 is a radial section taken in a vertical plane indicated approximately by the line 7-7 in FIG. 5.

FIGS. 8 and 9 are similar sections showing respectively different forms of needle-operating mechanism.

FIG. 10 is a small scale schematic plan showing means for raising and levelling the needles, for example to receive a transferred top.

FIG. 11 is a plan of the needle-operating cam ring shown in FIG. 8.

FIG. 12 is a partial section on the line 12-12 in FIG. 11.

FIG. 13 is an outside elevation of one of the cam assemblies shown in FIG. 11.

FIG. 14 is an outside elevation of another of the cam assemblies.

FIG. 15 is a section on line 15-15 in FIG. 11. FIG. 16 is a developed elevation showing cams on the cam ring of FIG. '11.

FIG. 17 is a developed plan view of the cams.

FIG. 18 is a plan of a control plate for sequence control.

FIG. 19 is an elevation of the control plate and associated parts shown in FIG. 18.

FIG. 20 is a plan of the upper end of a pattern drum controlling needle selection and yarn selection and also shows an arrangement for cross-connecting certain needles.

FIG. 21 is a partial right side elevation of the parts shown in FIG. 20.

FIG. 22 is a wiring diagram showing control circuits for the needle-operating mechanism shown in FIG. 9.

FIG. 23 is a plan of a sequence control plate for use in this embodiment.

FIG. 24 is a wiring diagram showing circuits for con trolling the needle-operating mechanism illustrated in FIGS. 7 and 8.

FIG. 25 is a view, partially in plan and partially in horizontal section, taken approximately on the line 25-25 in FIG. 1, illustrating yarn selection mechanism.

FIG. 26 is an elevation and partial section of the yarn selection mechanism, as viewed from the left of FIG. 25.

FIG. 27 is a side view of an article of hosiery made in accordance with the present invention.

FIG. 28 is a schematic developed view showing the pattern of the fabric illustrated in FIG. 27.

FIG. 29 is a stitch diagram of a small portion of the fabric.

In the drawings, the lines on which sections are taken are located as accurately as possible but should be considered as approximate. In order to simplify the drawings, certain parts of the machine are omitted in the various figures.

GENERAL CONSTRUCTION The machine in accordance with the invention has a frame on which the moving parts are supported, a needle bed, a series of independent needles reciprocally mounted on the needle bed, mechanism [for individually operating the needles, including an electromagnet for each needle, electric circuits controlling both the sequence of opera tion and the selection of the needles, yarn-feeding mecha: nism and preferably means for changing yarns during the operation of the machine.

The needle bed is shown in the form of a slotted cylinder 1 (FIG. 8) which is stationary in the sense of being non-rotating but preferably is supported for vertical endwise movement by a cylindrical sleeve portion 2 of the machine frame -3 (FIGS. 1 and 8). The needle cylinder 1 is movable vertically by means of a collar 4- and suitable connecting members 5 and a cam follower 6 (FIG. 1) which cooperates with cams 7 carried by the shaft 8 of the main pattern drum 9 of the machine. The vertical movement of the cylinder adjusts the length of the knitted stitch and also provides for lowering the cylinder relative to the needles when it is desired to transfer fabric on to the machine, as for example the rib knit top of a stocking.

A circular series of needles is provided on the needle bed, each needle 10 having a hook '11 and latch :12 at its upper end and one or more butts 13 at its lower end (FIG. 9). At the upper end of the cylinder, there is a sinker ring 14 carrying a circular series of radially slidable sinkers 15 which are moved in and out by means of suitable cam surfaces in a rota-ting and oscillating sinker cap '16. The latches of the needles are controlled by one or more latch rings 17 (FIG. 9).

NEEDLE-OPERATING MECHANISM The needle-operating mechanism may assume dilferen-t physical forms, three embodiments being illustrated in FIGS. 7, 8 and 9, respectively. In the form shown in FIG. 9, each needle is provided with an operating lever 20 which extends radially outwardly from the needle cylin der 1 and is pivoted at 21 on a stationary frame member 22. At its inner end, the lever 20 has a socket 23 that fits over the butt 13 of the needle. At its outer end, the lever has an armature 24 disposed between two

electromagnets

25 and 26 carried, respectively, by

stationary rings

27 and 28. When the magnet "25 is energized, it lifts the armature 24 to pull the needle down. The energizing of magnet 26 pulls downwardly on the armature 24 to raise the needle. Hence, by energizing selected magnets in predetermined sequence, selected needles can be raised to receive a yarn and then drawn down to knit it.

In order to raise and level all of the needles simultaneously, for example to transfer a rib knit stocking top on to the needles, a buffer ring 29 is raised beneath the inner end portions of levers 20 by means of interengaging cam portions on ring 29 and a cooperating ring 30 which is rotatable by means of a handle 31 (FIGS. 1 and 10*). The inner ends of the levers 20 are guided in their vertical movement by means of a stationary ring 32 having a series of vertical radial slots 33 in which the levers are received.

In the form as shown in FIG. 7, the needle-operating mechanism comprises an operating lever 35 for each needle. Each of the levers is pivoted at 36 on a bracket 37 carried by an upper ring 38 supported by means of posts 39 which project upwardly from radial ribs 40 projecting outwardly from the cylinder-supporting sleeve 2. At its inner end, the lever 35 has a socket portion 41 engaging the butt 13 of the corresponding needle. Intermediate its ends, each lever is provided with a rider 42 which is preferably formed of hardened material. A portion of the upper surface of each rider 4 2 is preferably rounded for smooth engagement by one or more cams 43 carried by a cam ring '44 which is rotatably supported by means of ball bearings 45. The cam ring 44 is driven in synchronism with a rotating yarn feed head (described below) and the number and position of cams 43 provided on the ring correspond to the yarn feeds. In the present embodiment, there are four yarn feeds which are equally spaced in a circumferential direction and four cams 43 likewise equally spaced. The cams 43 are substantially \/-shaped with flattened bottoms and are adapted to engage the riders 42 on the needle-operating levers 35 in either direction of rotation of the cam ring 44 to draw the needles down and thereby draw stitches of the yarn fed to the needles. The phase relation is such that the cams 43 follow the respective yarn feeds. The cam ring 44 is driven in any suitable manner, for example by means of a separate sprocket as described below in conjunction with FIG. 7 or by an arm 46 that projects downwardly from the yam-feeding head and acts on one or the other of spaced bumper members 47 on the ring 44, the spacing being such as to provide proper phase relationship between the cam ring and the yarn feed head in both directions of rotation. These screws provide suitable adjustment. The levers 35 are guided adjacent the riders 42 by means of a vertically slotted cylinder 48 which also supports a bearing ring 49 for the rotating cam ring 44.

When the needle-operating levers 35 are pressed down by a cam 43, each lever is held in its down position by means of a spring latch 51 which has a bifurcated upper end straddling the lever 35 and engaging the rider 42. The latch 51 is pivoted at 52 and a spring 53 tends to swing it in a clockwise direction (as viewed in FIG. 7) about its pivot. The latch 51 is swung in the opposite direction to release the needle-operating lever 35 by means of a rod 54 connected with the plunger-type armature 55 of a cylindrical electromagnet 56 supported by a bracket 57 on a stationary ring 58. A tension spring 59 acts between the lever 35 and the upper ring 38 to raise the lever when it is unlatched.

In this embodiment, the needles and operating levers are normally locked down in their lower position. By energizing selected ones of the magnets 56 in predetermined sequence, the corresponding levers are unl'atched and the needles are raised by springs 59. After receiving yarn for that particular fed, the needles are pressed down by one of the cams '43 acting on the operating levers which are again latched. If a magnet 56 is not energized, the corresponding needle holds its stitch and does not knit a new stitch in that course.

If it is desired to raise and level the needles for trans- \ferring, this can be done by mechanism like that described in conjunction with FIGS. 9 and =10. In this event, provision is made for disengaging the cams 43 from the riders 42, for example by making the riders slidable on the levers or by providing for the lifting or radial movement of the cams 43. Otherwise, certain needles would be held down by the cams. One end of the winding of each electromagnet 56 may, for convenience, be connected to a bus bar 64.

In the embodiment of FIG. 8, the needles are operated by radially projecting levers 60, each of which has a socket 61 at its inner end to receive the needle butt 13 and is pivotally mounted at its outer end 62 on a bracket 63 carried by the supporting ring 33. Upper arm 65 is pivoted on the bracket 63 at '66 and is connecteclwith the lever 60 by a pair of rods 67, one being shown, so that the lever 60 and arm 65 form a parallelogram linkage. A screw adjustment device 68 provides adjustment of the relative positions of the lever 66 and arm 65.

At its inner endnearest the needle cylinder-the arm 65 carries a roller 70 mounted on a shaft 71 that is telescopically slidable in the arm 65 and is pressed inwardly towards the needle cylinder by a spring 72. In its outer position, the shaft 71 is held against the spring pressure by means of a latch 73 engaging a detent 74 on the shaft. The latch 73 is pivotally mounted on the arm 65 at 75 and is pressed into engagement with the detent 74 by a light spring 76. The latch is released by means of a bell crank lever 77 pivoted at 78 on an extension of the bracket 63 and having an upwardly projecting portion 79 adapted to engage the rear end of latch 73 at a point adjacent the pivot 66 of arm 65. The other arm of the bell crank 77 extends downwardly and is connected by a wire or link 80 with the pivoted armature 81 of a two-pole electromagnet 82. When the magnet is energized, the latch 73 is released to permit the roller 70 to move in towards the cylinder and thereby be in a position to be engaged by cams carried by a cam ring described below. The roller 70 is subsequently cammed back to its outer position and held thereby the latch 73 until the magnet 82 is again energized.

On the needle-operating lever 60, there is a slider 85 carrying a horizontal roller 86 and a vertical roller 87. A spring 88 tends to move the slider in towards the needle cylinder. The slider is held in its outer position against the pressure of the spring by a latch 89, portions of which, in the showing of FIG. 8, are hidden behind an arm of crank 77 and a part of lever 60, which is pivoted on the lever 60 at 90 and has an upstanding portion 91 adapted to engage an adjustable screw 92 carried by the bracket 63. A spring 93 tends to hold the latch in engagement with a detent on the slider 85 when the lever is in its lower position. When the lever is moved upwardly a predetermined distance determined by the adjustment of screw 92, the engagement of upstanding portion 91 of the latch with the screw 92 causes the latch to release the slider 85, allowing it to move inwardly to a position in which roller 86 is engaged by cams described below. Cam surfaces are also provided to engage with vertical roller 87 to move the slider to its outer position, whereupon it is again held by the latch 89.

The cams that act on the lever 60 and arm 65 are carried by the rotating and oscillating cam ring 44 (of FIG. 8) and an associated outer cam ring 95 which is spaced from, and carried by, ring 44 by means of suitable brackets. These cam rings are rotated and oscillated in synchronism with the yarn-feeding head, for example by means of an arm 46, as in FIG. 7, or preferably by means of a chain sprocket '96 (FIG. 3) which is mounted on posts 97 projecting upwardly trom the cam ring 44 and driven by a chain from a sprocket on the control shaft 120 described below.

In the embodiment illustrated in the drawings, there are four complete sets of cams on the cam rings 44 and 95, the sets being equally spaced and-corresponding to the tour feeds of the yarn-feeding head. Moreover, since the machine is designed to work in reciprocation as well as in straight rotary movement, each of the cams is double-faced or there are two corresponding cams. Referring to FIGS. 8 and 11 to 17, the cams adapted to act on the roller 70 of arm 65 are carried by the outer c am ring 95 and comprise clearing cams 100, resetting cams 101 and levelling cams 1102. The clearing cams are so positioned that they act on the rollers 70 only when the rollers have been fired by release of the

latches

73 and 70, even when the latter are retracted. These cams are of such height as to raise the unselected needles so that their books are approximately level with the sinkers. This prevents the formation of undesirably large loops at the gore during widening and narrowing, for example in making the heel and toe pockets and in kitting diamond patterns.

The cams acting on the

rollers

86 and 87 on the lever 60 are carried by the inner cam ring 44 and comprise stitch cam-s 103 and a V-shaped resetting earn 104. The cams 103 are in such position radially that they do not engage the rollers 86 when the sliders are latched in their outer position. When the rollers are in their inner position, they are engaged by the stitch cams 103 to draw the needles down and thereby draw stitches of the yarn fed to the needles. Resetting cam 104 acts radially on the vertical rollers 87 to move the sliders to their outer position. As the needles and operating levers 60 have at this time been drawn down by the stitch earn 103, the sliders 85 are held in their outer position by the latches 89. The resetting cam .104 is slidable relative to the stitch cams 103, for example by being slidably mounted on a rib 106 that projects from the outer face of the stitch cams. It thereby assumes the position shown in solid lines in FIGS. 16 and 17 during rotation of the cam rings in one direction and the position shown in dotted lines during the other direction of rotation so that resetting cam at all times trails the active stitch cam. I

'I'bere are also provide V-shaped feeding cams 107 (FIGS. 11, 15, 16 and 17) which are carried by inwardly projecting portions 108 of the inner cam ring 44 and are adapted to engage either the inner ends of the levers 60 or additional butts on the needles just above these levers so as to lower all of the needles to a predetermined level to receive the yarn fed by the yarn-feeding means. It has been found that the needles should be lowered to a point where their latches are protected by the sinkers so that the yarn cannot accidentally get below the latches.

It has been found that with a four-feed machine such as that shown in the drawings it is not necessary to provide any shogging between the cam rings and the yarnfeeding head during reciprocation. As the yarn feeding points are disposed between two stitch earns, the needles are operated to draw stitches of the yarn by one stitch cam during rotation in one direction and by the stitch cam on the other side of the feeding point during rotation in the opposite direction.

The rotatable sinker cap 16 (FIG. 9) is driven from the cam ring 44 by means of an upwardly projecting arm 109 (FIGS. 11 to 13) which engages opposed bumper screws (not shown) that are adjustable to control the angular relation of the cam ring and the sinker cap in both directions of rotation.

The operation of the needle-actuating mechanism shown in FIG. 8 is as follows: When the electromagnet 82 is energized, the corresponding roller 70 is fired to its inner position where it is engaged by one of the clearing cams (FIGS. ll to 17) to raise the needle to clearing position. The raising of the needle-operating lever 60 releases latch 89 (-FIG. 8), allowing the slider 85 to move to its inner position so as to be engaged by a stitch cam 103 which draws the needle down to form a stitch. The roller 70 and slider 85 are reset by their corresponding

resetting cams

101 and 104. When a needle is not selected, i.e. when the corresponding magnet 82 is not energized, the roller 70 is raised slightly by the levelling cam 102 but not enough to release the latch 89 and not enough to clear the latch of the needle. The unselected needles hence hold their stitches.

NEEDLE SELECTION The selection of needles at each of the four feeds is eifected by a combination of sequence selection, which determines the sequence and timing of the needle operation, and pattern selection, which determines whether or I not a particular needle is to take the yarn and draw a new stitch at that feed.

Sequence Selection Sequence selection is provided by means of a series of devices for opening and closing the circuits that supply electric energy to the individual electromagnets in predetermined sequence one after the other. For convenience of terminology, these devices are referred to as circuit breakers although they may assume any suitable form, for example mechanical contacts, mercury switches or equivalent devices for stopping and starting the flow of current to energize the magnets or for varying the flow of current above and below a critical value required for energizing the magnets. By means of this sequence control, the magnets that control the needles are energized in predetermined timed relation to the rotation of the yarn feed. When knitting by reciprocation, the sequence control is automatically reversed each time the yarn reverses its direction.

In the embodiment of the invention illustrated by way of example in the drawings, sequence selection is obtained by the use of a plurality of control plates. The number of control plates may be varied as desired, depending upon the type of patterns it is desired to produce with the machine. -In FIGS. 2. and 3, five control plates numbered 111, 112, 113, 114 and 115, respectively, are mounted one above the other at the back of the machine. The plates are supported by suitable frame structure including a plurality of rods 116 which extend between the peripheries of the plates. The plates are formed of insulating material and each carries an arcuate series of electrical contact buttons 117 (FIGS. 18 and 19) which are connected by the circuits described below with the respective magnets for the individual needles. Preferably, each contact controls a particular magnet although in some instances a contact may control two or more magnets as desired by suitable cross-connection. In some instances, there may be a complete circular series of contacts, the number of contacts corresponding, for example, to the number of needles in the machine. In the embodiment illustrated in the drawings, the control plates are shown with approximately semi-circular series of contacts, the number of contacts on each plate being equal to, or slightly greater than, half the number of needles. In order to operate all of the needles, two of the control plates may be used simultaneously, one controlling half of the needles and the other the remaining half. Alternatively, the needles may be cross-connected so that each contact controls two needles, for example pairs of needles that are diametrically opposite one another. In some instances, as illustrated on control plate 115 (FIG. 24), there may be somewhat more than a semi-circle of contacts. Such a control plate may, for example, be used in reciprocating knitting, as in knitting heel and toe pockets of a stocking when it is desired to use more than half of the needles. Other arrangements of the contacts may be used to obtain the particular results desired. In addition to the contact buttons provided near the periphery of the control plates, each plate has a concentric inner slip ring 118. A rotatable shaft 120 extends up through alined holes in the control plates and carries brushes adapted to engage the slip rings 118 and contacts 117, the brushes being electrically connected with one another. The shaft 120 is driven from the main shaft 121 of the machine by means of bevel gears 122, a chain 123 and suitable chain sprocket so that the shaft 120 is always rotated and reciprocated in exact synchronism with the main shaft 121. The latter is driven in any suitable manner, for example by means of pulleys 124 (FIG. 3). The shaft 120 rotates in a clockwise direction, as viewed from the top, during operation of the machine in continuous circular motion.

Each of the control plates 111 and 112 (FIG. 24) is shown with a single set of brushes, e.g. a brush 126 contacting the slip ring 118 and a brush-127 engaging the contact buttons 117. The brushes are resiliently carried by an arm 128 which projects radially from an insulating collar 129 that is mounted on, and rotates with, the shaft 12$. Provision is preferably made for adjusting the brush arms angularly with respect to the shaft so as to vary the phase relation of the arms to one another and to the shaft.

Control plates

113, 114 and (FIG. 24) each have a brush engaging the slip ring 11% and a pair of brushes adapted to engage the contact buttons 117. The two latter brushes are spaced a predetermined distance apart, for example a distance of twelve contact buttons, and are so arranged that in reciprocating motion the leading brush is in contact with the buttons While the trailing brush does not engage them. In the construction illus trated in the drawings (FIGS. 18 and 19) a split fiber collar 131 having a bushing 132 clamps on to a sleeve 133 that surrounds and rotates with the shaft 126'. The collar carries a radially projecting arm 134 on the lower side of which is resiliently mounted a brush 135 adapted to engage the inner slip ring 118. A cross arm 136 is pivotally mounted at the outer end of the radial arm 134 and carries spring-pressed brushes 137 and 138- at its opposite ends. The extent of oscillation of the cross arm 136 is limited by engagement of a point 139 provided on the arm with an adjustable stop 140 on the radial arm 134. With this arrangement, the frictional engagement of the brushes with the control plate and contact buttons automatically rocks the cross arm 136 upon reversal of the direction of rotation so that the leading brushes only contact the buttons. This assures that the needles are properly raised to receive the yarn in both directions of rotation.

Provision is made for lifting the brushes of at least certain of the control plates when the respective plates are not in use. While the drawings illustrate mechanism for raising the brushes of control plates 112 and 113 (FIG. 3), it will be understood that similar or other mechanism may be provided for raising any desired ones or all of the brushes. The brush-lifting mechanism shown in the drawings comprises a bell crank 142 pivoted on a suitable support at 143 and having a forked arm 144 engaging a collar 145 on the sleeve 133 (FIG. 18) that carries the brushes, the sleeve being rotatable with, but axially slidable on, the shaft 120. The other arm of the bell crank is connected by a link 146 with a rocker 147 which is pivoted at 148 and has a nose portion adapted to be engaged by suitable cams on the main pattern drum 9. When the nose of the rocker 147 rides up on a cam, the brush assembly if lifted by the bell crank 142.

Means is provided for switching any desired ones of the control plates into the needle-operating circuits so that the sequence of operation of the needles may be controlled by one or another of the control plates or by two or more plates in combination. This makes it possible readily to vary the sequence of operation of the needles, for example when knitting difierent parts of an article or when knitting difierent articles. As illustrated in the drawings (FIGS. 3, 5 and 24), the machine is provided with a series of switches 150, each consisting of a pair of contacts adapted to be pressed together by means of a pivoted rocker arm 151 adapted to be engaged by suitable cams on an extension of the main pattern drum 9. Each of said switches is connected in series between a source of electromotive force and the inner slip ring 118 of one of the control plates. When the rocker arm 151 is engaged by a cam, the corresponding switch is closed so that electrical energy is supplied through the slip ring to the brushes of the corresponding control plate. As the shaft 120 rotates, the brushes supply current sequentially to the contacts 117 since the brush that engages the slip ring 118 and the brush that engages the contacts are electrically connected. Where provision is made for lifting the brushes, as described above, it is not necessary to have a disconnecting switch 15G since the lifting of the brushes automatically opens the circuit. However, for greater flexibility of control, each control plate is preferably provided with a corresponding switch 150.

Pattern Selection Pattern selection is obtained by means of circuit breakers provided in the electrical operating circuits of the individual needles and opened and closed in accordance with a predetermined pattern or plan. The connections between the circuit breakers controlling needle selection and the circuit breakers which control the sequence of needle operation are such that a needle is operated only by the cooperation of both circuit breakers, i.e. when both circuit breakers are in proper position. In the machine illustrated in the drawings, the two circuit breakers are in series with one another so that current is supplied for operating a particular needle only when both circuit breakers are closed. Suitable patterning mechanism is provided for opening and closing the circuit breakers that control needle selection during the knitting of an article. Preferably, the arrangement is such that the needle selection can be changed for each course of the fabric. The patterning mechanism may assume different forms as, for example, a moving strip or sheet which may be perforated or may have magnetized and unmagnetized areas acting through suitable responsive media to open and close the circuit breakers controlling pattern selection. Alternatively, a strip or sheet may have areas of different opacity acting through light-responsive media to control the circuit breakers. However, the machine illustrated in the drawings has pattern selection circuit breakers controlled by a rotatable drum, having removable pins actuating the circuit breakers.

As shown in FIG. 1, the circuit breakers controlling pattern selection comprise a series of switches 153 mounted on a vertical supporting strip 154 which is preferably formed of insulating material. The switches may be of any suitable form, as, for example, contacts carried by spaced resilient leaves mounted on a suitable insulating strip or block. Switches of this typebut for a dilferent purpose-are illustrated in FIG. 21. Suitable terminals are provided for the Wiring connections described below. The contacts are normally open, the circuit being closed by pressing the spaced contacts together. There is preferably a pattern selection circuit breaker for each needle so that each needle can be individually controlled although in some instances it may be desirable or permissible to control two or more needles by a single circuit breaker. Conversely, a needle may be controlled by more than one circuit breaker, as, for example, in a multi-feed machine where it is desired to have one needle selection for one feed and a different needle selection for another feed.

The pattern selection circuit breakers are closed by means of a pattern-selecting drum 155 which is rotatable about an axis parallel to the strip 154 and has in its peripheral surface a multiplicity of holes into which pins can be inserted. The pins 156 are adapted to press on the adjacent leaves of the switches 153 so as to bring the contacts together and close the circuit. The pins are formed of insulating material or, alternatively, the pinengaging portions of the switches are insulated so as to maintain electrical insulation between the switches and the drum. The number and spacing of the horizontal rows of holes in the drum 155 correspond with the number and spacing of the switches 153. In the illustrated embodiment, the number of switches 153 is equal to the number of needles in the machine. The number of holes in each row may vary in accordance with the patterning desired but should preferably not be less than half the number of needles. To provide still greater patterning range, the number of holes in each horizontal row is increased and may, for example, be equal to the number of needles or even greater. In the preesnt emis racked once each revolution of the main shaft.

bodiment of the invention, there are three hundred holes in each row. By having the number of horizontal rows of holes and corresponding number of switches equal to the number of needles and by having the number of holes in each row equal to the number of courses in the patterned portion of the fabric being knit, it is possible to control each needle individually in the knitting of each course.

The pattern selection drum is rotated intermittently by means of a worm wheel in the form of a toothed ring 157 secured to the upper end of the drum and rotated by means of la meshing Worm 158 on a horizontal shaft 159 rotatably supported by suitable bearings (FIGS. 1, 2 and 5). The shaft 159 extends across the back of the machine and, at its opposite end, has a sprocket 160 driven by a chain from a sprocket 161 (FIG. 3) on a shaft 162 which also carries a gear 163 meshing with a larger gear 164 on a shaft 165. The shaft 165 is rotated intermittently by means of a ratchet 166 which is mounted on the shaft and is racked by a pawl 167 carried on a swinging lever 168 pivotally supported at 169 and having a cam portion 170 adapted to be engaged by one or more rollers 171 carried by a gear wheel 172 driven by an intermeshing gear on the main shaft of the machine. The frequency of racking of the ratchet is determined by the gear ratio between gear 172 and the main shaft and by the number of rollers 171. Preferably, the sprocket The racking of the ratchet 166 may be interrupted by means of an L-shaped blocking arm 173 which is swingable about the shaft 165 by linkage 174 actuated from the main pattern drum to a position in which it holds the swinging lever 168 out away from the rollers 171. The blocking lever 173 is held in this position by a detent 175 on a lever 176 which is swingable about a pivot shaft 177'. The lever 176 has a nose portion 178 adapted to be engaged by spaced projections on an auxiliary pattern chain 179 which runs on a sprocket 180 mounted on the shaft 165; the engagement of a projection on the chain with the nose portion 178 lifts the lever 176 so as to release the blocking lever 173 from the detent 175 and thereby free the swinging arm 168. A bell crank 18-1 actuated from the main pattern drum by suit-able linkage 182 has a yoke portion adapted to engage the lever 176 adjacent its pivot so as to shift the lever laterally, i.e. axially of the pivot shaft 177, so that the nose portion 178 is out of line with the chain 179 so as not to be engaged by the projections on the chain. When the lever 176 is shifted in this manner, it will continue to hold the arm 173 in a position to block the racking of the ratchet 166. Suitable springs or other means are provided for returning the various parts to their normal positions. When the ratchet 166 is racked, the shaft 1'59 is rotated and the worm 158 acts on the worm wheel 157 to move the drum 155 forward a distance equal to the space between successive holes in the peripheral surface of the drum. The worm locks the drum in the position to which it is moved and prevents any over-shooting. In order to release the drum so that it can be moved independently of the worm 158-, for example to time the machine, means is provided for engaging and disengaging the worm with the worm wheel 157. In the illustrated embodiment, the hearing at the end of shaft 159 adjacent the selecting pattern drum is movable toward and away from the drum by means of an eccentric 184 rotatable by means of a lever or handle 185.

The patterning potentialities of the machine are still further increased by the provision of a series of crossconnecting switches so that two or more needles, for example diametrically opposite needles, can be operated together. Since the pattern designs on the opposite sides of a tubular fabric are ordinarily alike, diametrically opposite needles may be controlled by the same row of pins on the selecting pattern drum. For example, if the machine has 108 needles, they can be controlled by using

Claims

7. A METHOD OF KNITTING A TUBULAR FABRIC ON A MULTIFEED KNITTING MACHINE BY RECIPROCATING KNITTING IN WHICH AT LEAST EIGHT THREADS FORM SEPARATE SECTIONS OF INDIVIDUAL COURSES, THE STEPS COMPRISING KNITTING, DURING A STROKE OF RECIPROCATION, THREAD AT EACH OF SAID FEEDS TO FORM SECTIONS OF SAID INDIVIDUAL COURSES AND KNITTING OTHER THREADS, DURING ANOTHER STROKE OF RECIPROCATION, AT SAID FEEDS TO FORM OTHER SECTIONS OF SAID INDIVIDUAL COURSES.