US3421344A

US3421344A - High-speed knitting machine

Info

Publication number: US3421344A
Application number: US515555A
Authority: US
Inventors: James D Moyer; Douglas C Lang
Original assignee: North American Rockwell Corp
Current assignee: Boeing North American Inc
Priority date: 1965-12-22
Filing date: 1965-12-22
Publication date: 1969-01-14
Anticipated expiration: 1986-01-14
Also published as: DE1585439A1; DE1785695A1; GB1126247A; DE1585439B2

Description

Jan. 14, 1969 J. D. MOYER r-:TAL 3,421,344

HIGH-SPEED KNITTING MACHINE Filed Dec. 22, 1965 Sheet f of 5 TLG- i.

United States Patent Oliice 3,421,344 HIGH-SPEED KNITTING MACHINE .lames D. Moyer, Wyomissing, and Douglas C. Lang, Reading, Pa., assignors, by mesne assignments, to North American Rockwell Corporation, Pittsburgh, Pa., a corporation of Delaware Filed Dec. 22, 1965, Ser. No. 515,555 U.S. Cl. 66--55 11 Claims Int. Cl. D04b 9/02; D04b 15/24; D04b `15/32 ABSTRACT OF THE DISCLOSURE A knitting machine having a liXed cylinder, needles in the cylinder, sinkers on the cylinder, an outer sleeve rotatable on the cylinder, an inner sleeve connected to the outer sleeve for rotation therewith Iand for axial movement relatively there-to, cam means on the inner sleeve for operating the needles and lmeans for axially adjusting the inner and outer sleeves relative to each other to vary operating movements of the needles in relationship to the sinkers. The cam means includes different portions for operating the needles at different speeds from a high stitch clearing level to a low stitch drawing level and different portions for again raising the needles at different speeds from the low to the high level.

This invention relates to knitting machines and more particularly to such machines having a plurality of circular knitting heads which are constructed in a manner to permit high speed operation of the stitch forming means to knit yarns into tubular fabric.

In circular knitting machines and particularly such machines having nonrotating or stationary needle cylinders the needles are operated by `cams carried on a cam sleeve or cylinder which is rotated by drive means relative to the cylinder and where variation in the length of the stitches is desired, such stitch length variation is obtained by adjusting the vertical position of a stitch supporting tube relative to the needle cylinder and cam sleeve or by adjusting the vertical position of the needle cylinder relative to the cam cylinder. Also in such machines the operating cams are adapted to operate the needles between a high level in which previously formed stitches on the needles are cleared below the latches thereof and a low stitch drawing position, the needles being raised by an upwardly inclined surface directly from the low stitch drawing position to the high level during which the new stitches are stripped downwardly on the needles t open the latches thereof and then to cleared Ipositions below the latches. Alternately the needles are raised by a rs-t inclined surface from the low level to a tucking level during which the new stitches open the latches and the needles then subsequently raised from the tucking level to the high latch clearing level by `a second upwardly inclined surface. From the high level the needles after taking yarn are lowered by a downwardly inclined surface to the low stitch drawing positions to draw yarn for new stitches during which lthe previously cleared stitches close the latches over the yarn for the new stitches and are stripped or knocked of the needles.

During the change in direction of movement of the needles in the cylinder the butts of the needles engage the inclined surfaces with an impact that tends to twist or bend them and this combined with the impact of the latches on the hooks of the needles as the needles are lowered causes fatigue in the butts and hooks resulting in breakage thereof. Furthermore, this fatigue and resulting damage to the needles increases rapidly as the speed of the machine is increased and actually is one of the primary factors in determining the most economical operating speeds of the machine.

3,421,344 Patented Jan. 14, 1969 An objec-t of the invention is the provision of means for operating the stitch for-ming means in a circular knitting machine having a stationary needle cylinder, which means includes an outer sleeve mounted on the needle cylinder for rotation relative thereto, an inner sleeve having cams for operating the needles of the machine through stitch forming movements in the cylinder, and means for adjusting the aXi-al position of the inner sleeve relative to the outer sleeve and needle cylinder to adjust the movements of the needles to vary the length of the stitches formed thereby. The rotatable outer sleeve is also provided with means for operating the sinkers and yarn guide means for feeding yarn to the needles.

Another object of the invention is the provision of means in a circular knitting machine for operating the needles through stitch forming cycles which means is adapted to accelerate and decelerate the rate of movement of the needles in portions of the stitch forming cycles in a manner that will permit greatly increased operating speeds without increasing the forces tending to cause damage to the needles.

A further object of the invention is the provision of means for operating the latch needles of a circular knitting machine through stitch drawing movements, which means includes cam members defining a closed path for operating the needles between a high stitch clearing level and a low stitch drawing position, the path having a first portion for rapidly lowering the needles at ta first speedto engage yarn fed to the needles in the hooks thereof, a second portion for lowering the needles `at a second speed which is less than the first speed as the previously formed stitches thereon close the latches of the needles,I a third portion for lowering the needles to the stitch drawing -position to `draw new yarn stitches at substantially the same speed yas the lirst speed, :a fourth portion for raising the needles to a level intermediate the stitch drawing position and clearing level at the same speed as the third speed to disengage the hooks of the needles from the new stitches, and -a fifth portion for raising the needles from the intermediate level to the stitch clearing level at a speed greater than the second speed and lat a speed less than the third speed.

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 of construction and combination of parts in cooperative relationship as hereinafter particularly pointed out in the claims.

In the drawings:

FIG. 1 is a plan view of a knitting unit including a plurality of knitting heads incorporating means in accordance with the invention;

FIG. 2 is a view on an enlarged scale of one of the knitting .heads of FIG. 1 and the driving means therefor;

FIG. 3 is a 'cross-sectional view on an enlarged scale of the knitting head of FIG. 2 taken on the line Iand in the direction of the arrows 3--3` of FIG. 2;

FIG. 4 is a view diagrammatically showing the operating paths of the needles and sinkers of the machine during stitch forming movements thereof;

FIG. 5 is a cross-sectional view on an enlarged scale taken on the line and in the direction ofthe arrows 5--5 of FIG. 2;

FIG. 6 is a view similar to FIG. 3 of a modified form of knitting head, the head being partly shown in cross section and partly shown in elevation;

FIG. 7 is a developed view of the needle operating cam path of the knitting heads as seen looking outwardly from the interior of the head; and

FIG. 8 is a view similar to FIG. 7 showing a modified form of cam path for operating the needles.

Referring to FIG. 1 of the drawings there is shown a machine including a base or frame 11 for supporting a plurality of circular knitting heads 12 of the stationary cylinder type, and a yarn rack 15 supported on the frame for mounting a plurality of yarn pirns or bobbins 16 above the knitting heads for supplying yarns thereto. The yarn is fed from the pirns associated with each knitting head around a rotating feed roll 17, through a guide eyelet 20` carried in arm 21 supported on the rack 15 and from the eyelet 20 to a guide tube 22 (FIG. 5) carried in a rotating yarn feed ring 25 of the head. The feed roll and its operating means forms no part of the instant invention and may be of any suitable construction to provide positive advance of the yarn from the pirns to the knitting heads.

Each knitting head 12, which is constructed for high speed operation to convert both single and multifilament yarns into tubular fabric, includes a base member 26 (FIG. 3) secured to an upper wall 28 of the frame 11 as by screws 27 and a sleeve portion 30 adapted to receive the lower end of a needle cylinder 31. The cylinder 31 is fixed against both axial and rotative movement on the sleeve portion by engagement of one or more thumb screws threadably carried in the cylinder, one of which is shown at 32 in FIG. 3, with the sleeve portion. The cylinder 31 is provided with slots 35 for pivoted latch needles 36 which are raised and lowered in the slots through knitting movements by means of and in the manner hereinafter set forth in cooperation with sinkers 37 to form yarn into stitches of the tubular fabric. The sinkers are guided for sliding movement between the needles in radially extending slots 40 formed in an outer sinker ring 41 secured to an outer surface of the cylinder 31 at the upper end thereof and in aligned slots 42 formed in an inner sinker ring 45 secured in adjusted position to an inner surface of the cylinder in a usual manner.

The needles 36 are operated through their knitting movements yby a rotatable cam system (FIG. 7) which acts on butts 46 of the needles, the system including a lower cam ring 47, an upper cam member 50 and an upper guard member 51. The upper cam member `50 and lower cam ring 47 are provided with complementary surfaces adapted to form a closed path or track in which the needle butts 46 move to raise and lower the needles in the cylinder including a first horizontal portion 52 which positions the needles at a high level to clear previously formed stitches below the latches thereof (see also FIGS. 4 and 5), and a downwardly extending portion 55 for lowering the needles at a first or thigh speed as the yarn is fed thereto through the guide tube 22 of the yarn feed ring 25 to engage the yarn in the hooks of the needles and prevent ballooning of some or all of the individual filaments of the yarn. The portion 55 of the closed track is followed by a downwardly extending portion 56 for lowering the needles at a second speed which is greatly decelerated from the first speed as the cleared stitches close the latches and the latter portion is followed by a downwardly extending portion 57 to lower the needles at substantially the same speed as the first speed to a low point 59 to draw new stitches and to knock over the previously formed stitches from the needles. Slightly before the needles are lowered by portion 57 the sinkers are retracted, by means hereinafter set forth, so that the stitches are drawn by the needles over the sinkers in front of the nebs thereof in the conventional manner.

From the low point 59 the needles are raised at a speed substantially the same as the first or high speed by an upwardly extending portion 60 to a position 61 intermediate the high level and low point of the track. During this rise of the needles to the position 61 the sinkers are moved inwardly to hold the new stitches and to strip them downwardly slightly on the portions of the needles `between the hooks and latches thereby relieving the pressure ofthe needle hooks on the new stitches. The needles are then raised at a third speed, which is intermediate the first and second speeds, by an upwardly extending portion 62 from the position 61 to a high horizontal portion 65 which is at the same level as portion 52, the new stitches opening and then being cleared below the latches of the needles. Alternately, as shown in the modification of FIG. 8, the cam track may include a horizontal portion 63 intermediate the upwardly extending

portions

60 and 62 to momentarily maintain the needle at the level of the intermediate position 61 while several of the following needles draw their stitches. The guard member 51 and lower ring member 47 form a closed track to `maintain the needles at the level of the

portions

52 and 65 of the track. As will be seen in FIG. 7, except for narrow spaces 66 between the ends of the cam member 50 and guard member 51, which are provided to permit the installation of the needles in and their removal from the cylinder, the

members

50 and 51 and lower cam ring 47 form a completely closed path of movement for the needles.

The lower cam ring 47, cam member 50 and guard member 51 are secured in fixed positions on inner surfaces of the inner sleeve 70 mounted in a bore 71 in an outer sleeve 72. The sleeve 72 is mounted for rotation on ball bearings 75 carried on a reduced portion 76 of the needle cylinder 31 between a shoulder 77 on the cylinder and a positioning ring secured to the reduced portion 76 as by set screws 81. A key 82, secured to the outer surface of the inner sleeve 70 by screws 85, interfits in a slot 86 in the outer sleeve 72 to prevent rotation of the inner and outer sleeves relative to each other `but permits axial movement of the inner sleeve in the outer sleeve in the manner and for purposes 'hereinafter set forth.

At its upper end the inner sleeve 70 is provided with screw threads 87 for adjustably receiving a correspondingly threaded nut 88 mounted in an annular recess or bore 90 in the outer sleeve 72 between a shoulder 91 at the lower end of the recess and a snap ring 92 carried in an annular groove 93 in the recess (FIG. 3). The nut 88 is provided with a series of holes, one of which is shown at 95, in the outer periphery thereof and one or more elongated slots 96 in the outer sleeve 72 permits insertion of a tool into the holes to rotate the nut to adjust the vertical position of the sleeve 70 and members 47, `50 and 51 thereon in relationship to the sinkers 37 to thereby vary the length of the stitches drawn by the needles 36. A set screw 97, threadably carried in the outer sleeve 72, is provided to secure the nut 88 in adjusted position on the inner sleeve 70.

The sinkers 37 are provided with butts 100 (FIG. 3) which are acted on by an inner cam 101 to move the sinkers outwardly during stitch drawing movements, as hereinbefore set forth, so that the needles draw their stitches over the sinkers in front of the nebs thereof and an outer cam 102 to again move the sinkers inwardly following stitch drawing movements to hold the new stitches beneath the nebs as the needles are again raised to clearing level (see also FIG. 4). The

cams

101 and 102 are secured by screws 103 to a plate 104 which is in turn secured by screws 105 in a slot 106 formed in an upper horizontal flange 107 of an inverted L-shaped ring member 108 (FIGS. 2 and 3). A flange 110 extending downwardly from the upper flange 107 of the ring member 108 is dimensioned to intert an upwardly extending annular flange 111 on the outer sleeve 72. Set screws 112, threadably carried in the upper flange 107 for engagement with the upper surface 0f the flange 111 on the sleeve 72, are provided to adjust the vertical position of the ring member 108 and

cams

101 and 102 thereon on the sleeve 72 so that the

cams

101 and 102 only engage the butts of the sinkers, and clamping screws 115, threadably carried in the flange 111 and extending through slots 116 in the flange 110 of the ring member, are provided to permit relative rotary adjustment between the ring member and ange 111 of sleeve 72 and to releasably secure the ring member on the flange 111, after both vertical and rotative adjustments, for rotation with the outer sleeve. The yarn feed rin-g 25, hereinbefore referred to, is secured to the upper ange 107 of the ring member 108 as by screws 117 for rotation with the member 108 and sleeve 72, and has a lip 118 extending inwardly and downwardly with an inner surface forming the lower part of an annular wall defining a circular opening 120 adapted to receive the cleared needles, the lip acting to fully open latches inadvertently partially closed as the needles are raised to clearing level and to maintain the latches open until yarn is fed into the hooks of the needles through the guide eye 22 in the yarn feed ring. n

The sleeve 72 of each knitting head 12 is provided with an annular bead 121 grooved to receive a V-shaped belt 122 connected to a pulley 125 carried on the shaft of a motor 126 secured in fixed position to the underside of the wall 28 of base 11 (FIGS. 2 and 3). The pulley 125 is ofthe type having a iixed half and a spring loaded movable half which is adapted to be adjusted relative to the fixed half by pressure applied by a take-up roller 127 on one of the runs of the belt between the sleeve and pulley to vary the effective driving diameter of the pulley and the speed at which it drives the sleeve 72. The takeup roller 127 is carried on one arm 130 of a lever 131 pivoted on a stud 132 mounted in fixed position on the base 11. A second arm 135 of the lever pivotally carries a threaded nut 136 for engagement with a correspondingly threaded end of a rod 137. The other end of the rod 137 is rotatably carried in a bracket 140 which is in turn pivotally mounted on the base 11 (FIG. 2). Collars 139 secured on the rod 137 in abutting engagement with opposite sides of the bracket 140 prevent axial movement of the 4rod relative to the bracket. A feeler finger 141 having one end secured to the nut 136 has its other end in reading engagement with speed indicator markings 142 on a plate 145 secured to the bracket 140. The rod 137 is provided with a knob 146 whereby the rod may be rotated to adjust the take-up action of the lever 131 and roller 127 on the belt 122 to vary the driving relationship between the fixed and movable portions of the pulley 125.

In the modified form of the knitting head, shown in FIG. 6, the base member 26 is provided with a slot 150 adapted to receive one arm 151 of a lever 152 pivotally mounted on a -pin 155 carried at the underside of the base member. At its free end the arm 151 h'as a nose portion 156 for engagement in a slot 157 formed in the inner surface of the cylinder 31, the nose and slot cooperating to maintain the cylinder in fixed position on the base member 26. A second arm 160 of the lever 152 threadably carries a thumb screw 161 which cooperates with the wall 28 of the base 11, when the thumb screw is turned in one direction to turn the lever 152 counterclockwise and move the nose portion 156 into the slot 157 and into holding engagement with the needle cylinder. On the other hand movement of the thumb screw 161 in the opposite direction permits manual movement of the lever 152 in a clockwise direction to remove the nose portion 156 from the slot 157 when itis desired to remove the needle cylinder 31 and associated parts from the base member 26. i

Also in this embodiment of the invention the cam ring 47, cam member 50 and guard member 51 are secured to inner surfaces of an inner sleeve 165 which is mounted in the bore 71 of the sleeve72 in the same maner as inner sleeve 70. The sleeve 165 has an upper flange 166 extending outwardly into the recess 90 in the sleeve 72 between the shoulder 91 and the snap ring 92. The flange 166 is provided with spaced recesses such as indicated at 167 adapted to receive springs 170, the springs acting between the bottoms of the recesses and the snap ring 92 to bias the inner sleeve 165 downwardly to maintain the lower end thereof in engagement with rods 171 mounted for vertical movement in holes 172 in the sleeve 72. The lower ends of rods 171 rest on a ball type thrust bearing 173 or the like carried in a ring member 175 threadably carried on a portion 176 of the base member 26 whereby upon rotation in one direction or the other the rin-g member acts on the rods 171 to adjust the vertical position of the inner sleeve and

members

47, 50 and 51 thereon relative to the sinkers 37 to in turn vary the length of the stitches drawn by the needles 36. A set screw 177 is carried in the base member 26 for engagement with the ring member to lock it in adjusted position on the portion 176.

It is believed to be obvious from the foregoing that the knitting machine of the invention is constructed in a manner to permit operation of the stitch forming means at high speeds without increasing the damage to 'such means above that normally occurring in machines operating at conventional speeds. Also the machine, which is adapted primarily for the knitting of continuous lengths of tubular fabric, is constructed to permit adjustment of the operat ing speed thereof, to permit the ready adjustment of the operating means for the stitch forming means to vary the stitch length of the fabric formed thereby and to facilitate the ready removal of the complete knitting head `when replacement of worn or damaged parts is required or when -a head having one needle count is to be replaced by a head having a different needle count.

It will be understood that the improvements specifically shown and described by which the above results are obtained can be changed and modified in various ways without departing from the invention herein disclosed and hereinafter claimed.

What is claimed is:

1. In a knitting machine having a cylinder, a base member, means for releasably mounting said cylinder in fixed position on said base member, slots in said cylinder for pivoted latch needles, sinkers, means on said cylinder for mounting said sinkers for cooperation with said needles, an outer sleeve member rotatably mounted on said cylinder, an inner sleeve mounted in said outer sleeve member, means for connecting said inner and outer sleeves to cause rotation of said inner sleeve with said outer sleeve while permitting axial movement of said inner sleeve relative to said outer sleeve, yarn feeding means mounted on said outer sleeve for rotation therewith, cams mounted on said outer sleeve for rotation therewith for operating said sinkers, cam means on said inner sleeve for operating said needles in said cylinder in cooperation with said sinkers to form yarn into stitches of a4 tubular fabric, means for axially adjusting said inner and outer sleeves relative to each other to vary the stitch. forming movements of said needles by said cam means in relationship to said sin'kers to thereby vary the length of the stitches formed lby said needles, and means for rotating said outer sleeve.

2. |In a machine according to claim 1 in which said means for axially adjusting said inner and outer sleeves relative to each other includes a ring member and means connecting said ring member and said inner sleeve whereby upon rotation of said ring member said inner sleeve is axially adjusted relativeto said outer sleeve.

3'. In a machine according to claim 2 in Iwhich said connecting means comprises cooperating screw threads on said ring member and said inner sleeve, and there is means on said outer sleeve for holding said ring member against axial movement relative to said outer sleeve wlhereby upon rotation of said ring member relative to said inner sleeve said screw threads act to axially adj-ust said inner and outer sleeves relative to each other.

`4. In a machine according to claim 2 in lwhich said connecting means comprises cooperating screw threads on said ring member and said base member and means for supporting said inner sleeve on said ring member.

5. In a machine according to claim 4 in which said supporting means is carried in said outer sleeve and there is spring means for holding said inner sleeve in engagement with said supporting means.

6. yIn a machine according to claim l, in which said cam means on said inner sleeve for operating said needles to form yarn into stitches includes a lower cam ring, and an upper cam member, said lower cam ring and said upper cam member havin-g complementary surfaces defining a closed path for operating said needles including a first horizontal portion for positioning said needles at a high level in which previously formed stitches on said needles are cleared below the latches thereof, a first downwardly extending portion for lowering said needles at a first speed from said high level after yarn is fed thereto to engage said yarn in the hooks of said needles, a second downwardly extending portion for loiwering said needles at a second speed which is slower than said first speed as said cleared stitches close the latches of said needles, a third downwardly extending portion for lowering said needles to a low stitch drawing position at substantially the same speed as Said first speed to draw new stitches and to knock off previously formed stitches from said needles, a first upwardly extending portion for raising said needles at a speed substantially the same as said first speed from said low stitch drawing position to a position intermediate said high level and said low stitch drawing position at which time said new stitches are lowered slightly on said needles, and a second upwardly extending portion for raising said needles at a third speed from said intermediate position to a second horizontal portion rwhich is at the same level as said .first horizontal portion to clear said new stitches below the latches of said needles.

7. A machine according to claim 6 in which said closed path includes a third horizontal portion intermediate said first and second upwardly extending portions for momentarily maintaining said needles at said intermediate position.

8. A machine according to claim 1 in 'which there is means for adjusting the vertical position of said sinker operating caims on said outer sleeve, and means for releasably securing said sinker operating cams to said outer sleeve in adjusted vertical position, said -releasably securing means also permitting relative rotative adjustment of said sinker operating calms and said outer sleeve.

9. In a knitting machine having a cylinder, slots in said cylinder for pivoted latch needles, sinkers, means for mounting said sinkers on said cylinder for cooperation with said needles, yarn feeding means for feeding yarn to said needles, and cam means for operating said needles to form yarn fed thereto into stitches of a tubular fabric including a lower cam member, and an upper cam member, said lower and upper cam members having complementary surfaces defining a closed path for operating said needles including a first horizontal portion for positioning said needles at a high level in which previously lformed stitches on said needles are cleared below the latches thereof, a first downwardly extending portion for lowering said needles at a first speed from said high level after yarn is fed thereto to engage said yarn in the hooks of said needles, a second downwardly extending portion for lowering said needles at a second speed which is slower than said first speed as said cleared stitches close the latches of said needles, a third downwardly extending portion for lowering said needles to a low stitch drawing position at substantially the same speed as said first speed to draw new stitches and to knock off the previously formed stitches from said needles, a first upwardly extending portion for raising said needles at a speed substantially the same as said first speed from said low position to a position intermediate said high level and said low stitch drawing position at which time said new stitches are lowered slightly on said needles, and a second upwardly extending portion for raising said needles at a third speed from said intermediate position to a second horizontal portion which is at the same level as said first horizontal portion to clear said new stitches below the latches of said needles, the movement of said needles at said third speed being intermediate the movement of said needles at said first and second speeds.

10. In a machine according to claim 9 in which said closed path includes a third horizontal portion intermediate said first and second upwardly extending portions for momentarily maintaining said needles at said intermediate position.

11. In a knitting machine having a cylinder, a base member, means for mounting said cylinder in fixed position on said `base member, slots in said cylinder for pivoted latch needles, sinkers, means on said cylinder for mounting said sinkers for cooperation with said needles, an outer sleeve rotatably mounted on said cylinder, means for rotating said outer sleeve, an inner sleeve mounted in said outer sleeve, means for connecting said inner and outer sleeves to cause rotation of said inner sleeve with said outer sleeve while permitting axial movement of said inner sleeve relative to said outer sleeve, yarn feed means rotatable with said outer sleeve, cams rotatable with said outer sleeve for operating said sinkers, cam means on said inner sleeve for operating said needles in said cylinder in cooperation with said sinkers to form yarn into stitches of a tubular fabric, and means for axially adjusting said inner and outer sleeves relative to each other to vary the stitch forming movements of said needles by said cam means in relationship to said sinkers to thereby vary the length of the stitches formed by said needles, said axially adjusting means including a ring member and means connecting said ring member and said inner sleeve whereby upon rotation of said ring member said inner sleeve is axially adjusted relative to said outer sleeve.

References Cited UNITED STATES PATENTS 460,502 9/1891 Davis 66-107 670,892 3/1901 Clarke 66-55 1,184,501 5/1916 Williams 66-107 XR 2,016.870 10/1935 Me-iwald 66-12 XR 2,067,733 1/1937 Robaczynski 66-57 XR 3,095,717 7/1963 Coile 66-8 FOREIGN PATENTS 955,841 7/ 1949 France.

557,606 8/1932 Germany.

623,170 12/ 1935 Germany.

190,791 12/ 1922 Great Britain.

69,351 1/ 1952 Netherlands.

WM. CARTER REYNOLDS, Primary Examiner.

Us. C1. x.R.