US2863310A

US2863310A - Yarn severing means for knitting machines

Info

Publication number: US2863310A
Application number: US655222A
Authority: US
Inventors: Clifford F Miller
Original assignee: Textile Machine Works
Current assignee: Textile Machine Works
Priority date: 1957-04-26
Filing date: 1957-04-26
Publication date: 1958-12-09
Anticipated expiration: 1975-12-09

Description

Dec. 9, 1958 c. FQMILLER 2,853,310

YARN SEVERING MEANS FOR KNITTING MACHINES Filed April 26, 1957 5 Sheets-Sheet l INVENTOR. U/fi'om' E Miller ATTORNEY.

2,863,310 YARN SEVERING MEANS FOR KNITTING MACHINES Filed April 26, 1957 C. F. MILLER Dec. 9, 1958 5 Sheets-Sheet 2 I NVEN TOR. C/ifierd f' Mil/er ATTORNEY.

Dec. 9, 1958 C(F. MILLER 2,863,310

YARN SEVERING MEANS FOR KNITTING MACHINES Filed April 26, 1957 5 Sheets-Sheet 3 FIG... L.

30 40 (0 40 52mg I r l gu'figll;, 42 a 42 I 45 45 I I 36 L 36 4/ l 36 V fl a 9 E I 7? f a/ a5 26 IN VEN TOR.

ATTORNEY. E

Clifford E Mf/ler YARN SEVERING MEANS FOR KNITTING MACHINES Filed April 26, 1957 C. F. MILLER Dec. 9, 1958 5 Sheets-Sheet 4 IN V EN TOR. V. C/ffiom E Mi/ler A TTORNE Y.

9, c. F. MILLER 2,363,310

YARN SEVERING MEANS FOR KNITTING MACHINES Filed April 26. 1957 5 Sheets-Sheet 5 Fl l E] /2/ i5 ATTORNEY.

United States Patent YARN SEVERING MEANS FOR KNITTING MACHINES Clifford F. Miller, Hamburg, Pa., assignor to Textile Machine Works, Wyomissing, Pa., a corporation of Pennsylvania Application April 26, 1957, Serial No. 655,222 Claims. (Cl. 66145) This invention relates to full-fashioned knitting machines and more particularly to means for severing yarns extending between holding means fixed to the machine and fabric blanks.

In multi-section knitting machines of the type for knitting full-fashioned fabric blanks such as for stockings, yarns are fed by carriers to the loop forming elements of the machine to be formed thereby into the loops of the fabric blanks. The carriers are normally positioned in inactive position beyond either end of the loop forming elements with the ends of the yarns, which extend from the carriers, attached to holding means, the carriers being moved to active positions to feed their yarns into the fabric in any desired sequence. In conventional operations following the knitting of a newly introduced yarn into a few courses of the fabric, the yarn extending between the fabric edge and the holding means must be manually severed close to the fabric edge. Also, when these yarns are removed from knitting action the yarn extending between the fabric and carrier is severed and the end of the yarn from the carrier again attached to the holding means. These operations of severing and attaching the yarn to the holding means are usually performed manually and when it is considered that there is provision on the machine for introducing into the fabrics and removing therefrom up to nine dififerent yarns in each section of the machine it will be obvious that a considerable amount of time and effort is expended in these non-productive operations.

Heretofore, attempts were made to reduce the number of manual operations by providing means to automatically sever the yarns following their introduction into a fabric but in order to avoid interference with the knitting elements and fabricit was necessary to position such severing means beyond the ends of the rows of knitting elements and hence beyond the widest portions of the fabric. While this arrangement is effective with respect to yarns introduced into the widest portion of the fabric, such as welt yarns, the point of the fabric at which the reinforcing yarns are introduced is comparatively narrow and the severing of the yarn beyond the ends of the knitting elements would leave undesirably long yarn ends attached to the fabric which would have to be removed by a further operation before the joining of the edges of the fabric blank in a usual manner. Consequently, the reinforcing and any other yarns introduced at the narrow portions of the fabric would still have to be manually severed with the result that only a few of the many manual operations were eliminated.

-It it an object of the invention to provide a knitting machine with means for severing yarns at points closely adjacent to the selvages of the wide and narrow portions of the fabric at which the yarns are introduced into the fabric.

Another object of the invention is to provide a knitting machine with means for severing yarns, which means is movable from inactive to active positions to intercept and sever the yarns closely adjacent to the selvages of the wide and narrow portions of fabric at which the yarns are introduced into the fabric.

A further object of the invention is to provide a knitting machine with means for severing yarns. closely adjacent to the selvages of wide and narrow portions of fabrics which means are movable from an inactive to active positions in a manner to prevent engagement of the severing means for the yarns at the narrow portions of the fabric with the wide portions of the fabric when the severing means for yarns of the latter portion is moved into active position.

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 pointed out in the claims.

In the drawings:

Figure l is a front elevational view of a portion of a multi-section full-fashioned knitting machine having yarn severing mechanism according to the invention applied thereto;

Fig. 2 is a view of the pattern mechanism of Fig. 1 and diagrammatically showing the electrical circuit and control means for the severing mechanism of the invention;

Fig. 3 is a cross sectional view on an enlarged scale taken on the line 3-3 of Fig. 1;

Fig. 4 is a plan view on an enlarged scale of a knitting section of the machine shown in Fig. 1 and diagrammatically showing a portion of a fabric formed by said section;

Fig. 5 is a view on an enlarged scale of the mechanism shown at the upper part of Fig. 3;

Fig. 6 is a view partly in section and partly in elevation taken substantially along the line 6-6 of Fig. 5;

Fig. 7 is an elevational view on an enlarged scale taken in the direction of the arrows 7-7 on Fig. 1, parts being shown in cross section;

Fig. 8 is a plan view taken in the direction of the arrows 8-8 on Fig. 5, parts being omitted and other parts being broken away and shown in cross section;

Fig. 9 is a cross sectional view taken along the line 99 of Fig. 5;

Fig. 10 is an elevational view on an enlarged scale of a portion of the mechanism shown at the right of Fig. 1;

Fig. 11 is a view taken from the right of Fig. 10, parts being broken away and shown in cross section;

Fig. 12 is a view of a portion of the mechanism shown in Fig. 10 but with the parts in different positions than in Fig. 10; and

Fig. 13 is a cross sectional view taken substantially along the line 13-13 of Fig. 10.

Referring to Figs. 1 and 3 of the drawings, there is shown a portion of a knitting machine of a well known type such for example as the Reading Full-Fashioned Knitting Machine illustrated in a Parts Catalog published in 1952 by the Textile Machine Works, for knitting stocking blanks, including transverse center frames 20, a front beam 21, a back beam 22, a center bed 25 and a front bed or table 26, the beams, beds and center frames together with end frames (not shown) forming the usual framework of the machine. Supported in the framework in each section of the machine is a bar 27 having a row of needles 30 for cooperating with sinkers 31 and dividers 32, carried for sliding movement in a sinker-head 35. The needles, sinkers and dividers, comprising the loop forming elements, are operated in a usual manner to form yarns 36 (Fig. 4) into the loops of the fabric by cams (not shown) carried on a camshaft 37 supported for rotation in the end and center frames. The yarns 36 3 are fed to the needles 30, sinkers 31 and dividers 32 by yarn carriers 40 which are mounted for reciprocating movement along the bar 27 in the usual manner.

In inactive or non-feeding position, theyarn carriers 40 are beyond the row of needles at both ends of the bar 27 (Fig. 4) and the ends of the yarns 36 extending from the carriers are attached to holding means 41 secured to the table 26. Following the movement ofa yarn carrier 40 from its inactive position to feed a yarn 36 to the needles 30 and to knit such yarn into the fabric blank, the yarn is severed between a selvage of the blank and the holding means 41 to which the yarn is attached. This severing must occur close to the selvages of the blank both at the wide or welt width and at the narrow or ankle width of the blank, the latter width being illustrated in Fig. 4.

For severing the yarns 36 introduced at the widest portion of the blank there is provided outer units 42 adjacent to and outwardly of the end needles at each end of the needle bar 27. Each of the units- 42 is provided with a wire element 4-5 which is adapted to be engaged by the yarns as the yarn carriers move from inactive positions to active positions to feed the yarns to the needles 30. The elements 45 are connected to an electrical circuit, as hereinafter set forth, which is adapted to energize and heat the Wire elements to a temperature sufiicient to burn or melt the yarns. Likewise, for severing the yarns introduced at the ankle width of the fabric, wire elements 46 are provided similar to the elements 45. The elements 46 are carried in inner units 47 spaced inwardly of the units 42 and closely adjacent to opposite selvages at the narrow Width portion of the blank. The

wire elements

45 and 46 are in the same electrical circuit and are simultaneously energized and heated.

When the yarns 36 are introduced to the needles 30 forming the widest portion of the fabric, the yarns engage the wire element 45 of the unit 42 at the side of the blank at which the yarn is introduced. When a yarn is introduced at the narrow portion of the blank, as the fabric is knitted and drawn in the take-up direction, the yarn engages the wire element 46 in one or the other of the units 47. In order to prevent engagement of such yarns introduced at the narrow width of the blank with the outer units 42, the latter are adapted to be moved along a vertical line betweeen inactive positions indicated by a dot-and-dash line A in Fig. 5, below the level of such yarns and active positions, indicated in full lines in Fig. 5, to intercept the yarns to be severed thereby, the units 42 being held in the lower positions during the introduction and the initial knitting of the yarns at the narrow width of the fabric. The inner units 47 are also movable vertically with the units 42 from inactive positions indicated by a dot-and-dash line B in Fig. 5, but as illustrated in Figs. 1 and 5, the inner units are normally at a lower level than the outer units. Hence, at the time the outer units are vertically raised sufficiently to be engaged by a yarn introduced at the wide portion of the fabric the inner units will only be raised to intermediate positions indicated by dot-and-dash line C in Fig. 5. In the intermediate position, the inner units 47 are below the level of the fabric and out of contact therewith as it is drawn in the take-up direction. When the inner units 47 are to become active they are raised to the full line positions of Figs. 1 and 5, in a manner hereinafter set forth.

For moving the outer units 42 along vertical paths each unit is secured to a plate-like bracket 50 which ispivotally connected by a pin- 51 to the free end of a lever 52 pivotally mounted on a shaft 55 supported for rotation in the machine frame. The lever 52 is'positioned axially of the shaft 55 between a pair of collars 56 fixed on the shaft, one of the collars having a finger 57 which is adapted to engage a projection 60 on the lever 52 (Figs. 6 and 7) as and for purposes hereinafter set forth.

An upper end 61 of the bracket 50 is guided for vertical movement in a slot 62 in a bracket 65 fixed by screws 66 to a bridge member 67 one of which is secured to the table 26 at opposite ends of the row of needles 30, the bridge members acting to support a welt bar (not shown) for movement toward and away from the needles in a usual manner. A pin 70 carried in the bracket 65 engages in a slot 71 in the upper end 61 of the bracket 50 (Figs. 5 and 9) the pin acting to maintain the unit in vertical position against the rear end of the bridge member 67 and to limit the upward movement of the unit, as hereinafter set forth. A spring 72 connected between a pin 75 in the lever 52 and a pin 76 in the bridge member 67 biases the lever 52 counterclockwise as viewed in Fig. 7.

Each inner unit 47 is carried on a stud 77 having a reduced portion 80 mounted for pivotal movement in a lever 81 secured to the shaft 55 (Figs. 6 and 8). As indicated in Fig. 5, the lever 81 is shorter than the lever 52 so that a rotative movement of the shaft 55 to raise the outer units 42 from inactive to active positions will only raise the inner units 47 from an inactive to an intermediate position as above set forth. The shaft 55 is given a further rotative movement to raise the inner units 47 to active positions, the shaft being operated to raise both outer and inner units by means and in a manner hereinafter set forth.

As shown in Fig. 8, the stud 77 engages one side face of the lever 81 and is maintained in such engagement by a collar 82 fixed on the portion 80 at the opposite face of the lever. The stud 77 is biased clockwise by a spring 85 connected between the lever 81 and the collar 82 (Figs, 5 and 8) to maintain the unit 47 against the rear end surface of the table 26. An. arm 86 fixed to the shaft 55 is connected by a link 87 to one arm 90 of a lever 91 pivotally mounted on a. shaft or stud 92 carried in a bracket 95' secured to the, front beam 21. The lever 91, which carries a roller type follower 100, is. biased clockwise by a spring 96, connected between the end of arm 90 and an arm 97 secured to the back beam 22, to engage the follower with

cams

101 and 102 carried on the camshaft 37, for purposes hereinafter set forth.

The follower is mounted on the lever 91 by means of a stud 105 and the follower is shiftable axially of the stud from an inactive position to align it with either of the

cams

101 and 102 by a shifter member 106 pivotally mounted on a stud 107 carried in the bracket 95. A forked lower end 110 of shifter member 106 straddles a rod 111 between a forked end portion 112 of a bracket 115 and an end portion 116 of a bracket 117 (Figs. 3, l0 and 11), the end portions of the brackets also straddling the rod and being slidable axially thereof. The

brackets

115 and 117 are fixed on a rod 120 which together with the rod 111 are mounted for sliding movement along the length of the machine in brackets 121 one of which is shown secured to the front beam 21 in Fig. 1. The

rods

111 and 120 are two of the usual rods for controlling various mechanisms of the machine which are operated by pattern levers one of which is shown at 122 for the rod 120. The pattern levers form a part of a conventional main pattern device 125 having a chain 126 with buttons for operating the pattern levers.

Prior to movement of a carrier 40 to feed its yarn to a wide portion of the fabric, such as in the welt or at the start of the leg, the lever 91 is biased by the spring 96 to the limit of its movement in a clockwise direction.

the follower 100 is at a level only slightly above the low.

portions of

cams

101 and 102 and the shaft 55 has been turned to the counterclockwise limit of its movement, as viewed in Fig. 5, to lower the

units

42 and 47 to their lowest position, as indicated by the dot-and-dash lines A and. B, respectively, the units 42 being moveddown wardly against the action of the spring 72 by engagement of the finger 57 with the projection 60 on the lever 52. Also at this time, as there is no button beneath the lever 122, the rod 120 is in the right hand position of Fig. 1 to which it is biased by a spring 131 connected between the rod and a fixed part of the machine, and the shifter member 106 positions the follower 100 to the right of the cam 101.

In preparation for the movement of a carrier 40 to introduce the yarn to the needle 30 to form the welt portion of the fabric, the pattern chain is operated to move a low button 132 beneath the lever 122 to shift the rod 120 toward the left whereby the follower 100 is also shifted to the left by the shifter member 106 to align it with the cam 101. As the follower 100 engages the earn 101 and rides to the high portion thereof, the lever 91 is actuated to turn the shaft 55 and finger 57 counterclockwise (Fig. 7) and the spring 72 turns the lever in the same direction to raise the units 42 to their high active positions as determined by engagement of the closed end of the slot 71 in the bracket 50 with the pin 70 and the inner units 47 are simultaneously raised to their intermediate positions as hereinbefore set forth (Fig. 5). The units 42 are maintained in the high position so that as the carrier is moved to feed its yarn to the needles the yarn engages the unit at the side of the section from which the yarn carrier was moved, and the unit is then energized and heated to sever the yarn as hereinafter set forth. i

The units 42 are maintained in the high position by a latch lever 135 which is pivotally mounted on a shoulder stud 136 carried in the bracket 95 (Figs. and 11). The latch lever 135 is biased counterclockwise by a spring 137 connected between the latch lever and a pin 140 in the bracket 95 as shown in Figs. 3 and 10, and has lower and

upper side projections

141 and 142, respectively, which are adapted to be brought beneath the end of the arm 130 of the lever 91 upon movement of the lever 91 by the

cam

101 or 102. Normally when the follower 100 is at the level of the low portions of the

cams

101 and 102 the end of the arm 130 engages the side of the latch lever 135 to hold the lever in the position of Fig. 12, which, as viewed in this figure, is turned slightly in the clockwise direction from the latching position. When a low button 132 causes the follower 100 to be shifted and aligned with the cam 101, as above set forth, the follower rides from the low to the high portion of the cam to raise the end of the arm 130 above the tower projection 141, and the spring 137 turns the latch lever 135 counterclockwise to position the lower projection beneath the end of the arm. As the follower 100 rides from the high portion toward the low portion of the cam 101 the end of the arm 130 is lowered to rest on the projection 141. When the follower 100 reaches its low level, the button 132 is removed from beneath the lever 122, and the rod 120 is shifted toward the right by the spring 131 to move the follower to the right out of alignment with the cam 101. I

Following the severing of the welt yarn, the

units

42 and 47 are preferably returned to their low inactive positions. For this purpose, another low button 132 is moved beneath the lever 122 to shift the rod 120 toward the left to again align the follower 100 with the cam 101. As the follower 100 rides to the high portion of the cam 101 the end of the arm 130 is raised slightly to disengage the projection 141 and the latch lever is turned clockwise to remove the projection 141 from beneath the end of the arm so that as the follower rides from the high toward the low portion of the cam the end of the arm is again lowered to engage the side of the latch lever as shown in Fig. 12. For so turning the latch lever 135 in the clockwise direction, the latch lever is provided with a member 145 which is mounted for sliding movement on pins 146 secured to the latch lever. The pins 146 pass through an elongated slot 147 in the member follower with the cam 102.

and have head portions 150 which'are adapted to hold the member in engagement with one face of the latch lever (Figs. 10 and 13). The member 145 is biased upwardly by a spring 151 connected between the member and a pin 152 in the latch lever 135 to engage the lower end of the slot 147 against the lower pin 146. A projection 155 on the member 145 is adapted to be engaged by a finger 156 projecting from the upper end of a lever 157 pivotally mounted with the latch lever 135 on the stud 136. A lower end portion 160 of the lever 157 is biased toward engagement with the bracket 117 by a spring 161 connected between the lever and a collar 162 secured to the rod (Fig. 10). In the position of the end of arm of the lever 91, shown in Fig. 12, a pin 165 carried in the arm engages and depresses the memher 145 to move the projection 155 out of the path of the finger 156 of the lever 157 for purposes hereinafter set forth.

When the rod 120 is shifted to the left to align the follower 100 with the cam 101 to effect the raising of the units 42 to the high active position, as hereinbefore set forth, the lever 157 is turned clockwise (Figs. 10 and 12) by the spring 161. At this time with the member 145 being depressed by the pin 165, the finger 156 will pass above the projection 155. As the end of arm 130 is raised above the lower projection 141 by the action of the cam 101, the spring 137 turns the latch lever to position the lower projection beneath the arm, the member at this time being held in depressed position by the finger 156. When the button is removed from beneath the lever 122 and the rod 120 moved to the right by the spring 131, the bracket 117 turns the lever 157 counterclockwise to disengage the finger 156 from the projection thereby permitting the spring 151 to raise the member 145 to align the projection with the finger (Fig. 10). During operation of the second button 132 to effect the return of the

units

42 and 47 to lower inactive positions, movement of the rod 120 to the left turns the lever 157 and finger 156 clockwise to engage the projection 155. When the arm 130 is disengaged from the lower projection 141 by the cam 101, as above set forth, the spring 161 continues to move the lever 157 clockwise to turn the latch lever 135 clockwise and remove the lower projection from beneath the arm. Continuing operation of the cam 101 lowers the arm 130 of the lever 91 to the position of Fig. 12, during which movement the pin engages and depresses the member 145 to disengage the projection 155 from the finger 156 thereby permitting the spring 137 to turn the latch member 135 counterclockwise to engage the side of the arm 130. When the button 132 is again removed from beneath the lever 122 the lever 157 is turned to its position of Fig. 12, when the rod 120 is moved to the right as above set forth.

In order to raise the units 47 to active positions, shown in Fig. 5, as distinguished from the intermediate positions indicated by the line C in Fig. 5, as previously referred to, to engage and sever a reinforcing yarn, following introduction of this yarn to the needles 30, a high button 166 on the chain 126 is moved beneath the lever 122 to move the rod 120 to the left to align the During operation of the cam 102 to rotate the shaft 55 through the greater distance necessary to raise the units 47 to active positions, the units 42 are also raised to active positions and due to the greater movement of the shaft, the finger 57 disengages the projection 60 (Fig. 7). However, because the

units

42 and 47 are raised at this time after the reinforcing yarn is introduced to the needles and knitted into the fabric, the length of yarn extending between the edge of the fabric and the holding means 41 is to the rear of the units 42, as indicated in Fig. 4, and will be unaffected thereby. This reinforcing yarn will then be carried forward with the fabric as it is knitted to engage one of the units 47 and be severed thereby.

Preferably, a few courses after a yarn is engaged with are heated so that the one engaged will sever the yarn. In order to energize and heat the wire elements, the

units

42 and 47 are connected in an electrical circuit, preferably of 110 volts, comprising main conductors 170 which are connected by leads 171 to a timer device 172 as diagrammatically shown in Fig. 2. The timer device 172 may be of any commercial type, such as the Agastat Timer, manufactured by the Elastic Stop Nut Corp., of Elizabeth, New Jersey, which is adapted to close the circuit and to hold it closed for predetermined time intervals. The timer device 172 is connected by leads 175 to an adjustable transformer 176 by means of which the voltage may be varied to increase or decrease the temperature of the

wire elements

45 and 46 of the

units

42 and 47, respectively. The transformer 176 is connected by leads 177 to the

units

42 and 47 and the units are connected to each other in series by leads 180. The timer device 172 is provided with a contact button 181 which is adapted to be engaged and operated by one of the pattern levers 122 of the pattern device 125 to close the circuit to the

units

42 and 47 when a button 182 on the chain 126 is moved beneath the lever.

From the foregoing it will be apparent that the arrangement and operation of the outer and

inner units

42 and 47 is such that at the times yarns are fed to the needles to form the widest portions of the fabric only the units 42 will be raised to the full line positions of Fig. to intercept the yarn as it is moved to feeding position, after which the unit is heated to sever the yarn. At this time, the inner units 47 although being operated with the outer units 42, are only raised to intermediate positions indicated by the line C in Fig. 5, in which positions the tops of the inner units are well below the level of the fabric as it is drawn away from the needles 3th by the take-up means of the machine. The inner units 47 on the other hand are raised to the active full-line positions of Fig. 5 after the yarns are fed to the needles to be formed into loops in the narrow portions of the fabric and although the outer units 42 are also raised at this time they will be in back of the yarns extending between the holding means and the narrow portions of the fabric. As the fabric is formed and drawn in the take-up direction, the yarns engage the units 47 and are severed thereby. Following each operation to sever yarn, the units are lowered to inactive position and remain in such inactive position until the pattern device again institutes an operation of the units to active position.

Of course, 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.

I claim:

1. In a straight knitting machine having knitting elements and carriers for feeding yarns to said knitting elements to be formed into fabric thereby, means for holding the ends of yarns extending from said carriers, and means for severing said yarns comprising outer severing units for intercepting and severing yarns between the selvages at a Wide portion of the fabric and said holding means, inner severing units for intercepting and severing yarns between the selvages of a narrow portion of the fabric and said holding means, and means for moving both outer and inner sets of units to positions in which one of the sets of units intercepts yarns while the other set of units is below the point of interception with yarns, and additional means for moving said other set of units to position to intercept yarns.

2. In a straight knitting machine having knitting elements and carriers for feeding yarns to said knitting elements to be formed into fabric thereby, means for holding the ends of yarns extending from said carriers, and means for severing said yarns comprising outer and inner sets of severing units, means for moving said sets of units 8 .to position said outer set of units to intercept andsever yarns between said holding means and a wide portion of the fabric, and means for further moving said inner set :of units to intercept and sever yarns between said holding means and a narrow portion -of'said fabric.

3. In a straight knitting machine having knitting elements and carriers for feeding yarns to said knitting ele. ments to be formed thereby into fabric, means for bolding the ends of ya'r-ns extending from said carriers, and means for severing said yarns comprisingouter and inner severing units, means for moving said units to position said outer units to intercept and sever yarns between said holding means and a wide portion of the fabric, means for moving said units to position said inner units to intercept and sever yarns between said holding means and a narrow portion of the fabric, and means for controlling the operation of said first and second mentioned moving means.

4. In a knitting machine having knitting element's, carriers for feeding yarns to said knitting elements to be formed into fabric thereby, means for holding the ends of yarns extending from said carriers, and means for severing the yarns including outer and inner severing units, means for vertically moving said units to positions in which only the outer units engage and sever yarns between said holding means and a wide portion of the fabric, and additional means for vertical-1y moving said units to positions in which said inner units engage and sever yarns between said holding means and a narrow portion of the fabric.

5. In a knitting machine having knitting elements, carriers for feeding yarns to said knitting elements to be formed thereby into fabric, means for holdingfthe ends of yarns extending fro-m said carriers, means for sever-- ing said yarns including outer and inner severing units, an operating shaft, connections between said shaft and said outer and inner units, cam means for operating said shaft to move said units to positions in which only said outer units engage and sever yarns between said holding: means and a Wide portion of the fabric, and a second cam for operating said shaft to move said inner units to position to engage and sever yarns between said holding means and a narrow portion 'of said fabric.

6. In a straight knitting machine having knitting elements, carriers for feeding yarns to said knitting elements to be formed thereby into fabric, means for holding the ends of yarns extending from said carriers, means for severing said yarns including outer and inner severing units, means for moving said units to position said outer unit to engage and sever a yarn between said holding means and a wide portion of the fabric, a second means for moving said units to position said inner unit to engage and sever a yarn between said holding means and a narrow portion of the fabric, and pattern means for controlling the operation of said first and second moving means.

7. In a straight knitting machine having knitting elements, carriers for feeding yarns to said knitting elements to be formed into fabric thereby, means for holding the ends of yarns extending from said fabric, means for severing said yarns including outer and inner severing units adapted to be heated to predetermined temperatures to sever said yarns, means to heat said units, means for moving said units to position said outer units to engage yarns between said holding means and a wide portion of said fabric, a second means for moving said units to position said inner units to engage yarns between said holding means and a narrow portion of the fabric, control means for operating said first and second moving means, and means for controlling the operation of said unit heating means.

8. In a knitting machine having knitting elements, carriers for feeding yarns to said knitting-elements to be formed thereby into fabric, means for holding the ends of yarns extending from said carriers, means for severing said yarns including outer and inner severing units, means for vertically moving said units to positions in which only the outer units engage and sever yarns between said holding means and a wide portion of the fabric, additional means for vertically moving said units to positions in which said inner units engage and sever yarns between said holding means and a narrow portion of the fabric, means for controlling the operation of said first and second moving means, and latch means for maintaining said outer and inner units in the positions to which they are moved by said first and second moving means to engage yarns for predetermined time intervals.

9. In a straight knitting machine having knitting elements, carriers for feeding yarns to said knitting elements to be formed into fabric thereby, means for holding the ends of yarns extending from said carriers, means for severing said yarns including outer and inner severing units, means for moving said units from inactive positions to positions in which only the outer units are active to engage and sever yarns between said holding means and a wide portion of the fabric, additional means for moving said units from inactive positions to positions in which said inner units are active to engage and sever yarns between said holding means and a narrow portion of the fabric, means for controlling the operation of said first and second moving means, latch means for maintaining said outer and inner units in active positions for predetermined time intervals, means for operating said latch means to latch said outer and inner units in active positions, and pattern means for operating said latch means to release said units for return to said inactive positions.

10. In a straight knitting machine having knitting elements, carriers for feeding yarns to said. knitting elements to be formed into fabric thereby, means for holding the ends of yarns extending from said carriers, means for severing said yarns including outer and inner severing units, means for moving said units from inactive positions to positions in which only the outer units are active to engage and sever yarns between said holding means and a wide portion of the fabric, additional means for moving said units from inactive positions to positions in which said inner units are active to engage and sever yarns between said holding means and a narrow portion of the fabric, means for controlling the operation of said first and second mentioned moving means, latch means for maintaining said outer and inner units in said active positions for predetermined time intervals, pattern means, a control member on said latch means, having a first position in which said latch means is permitted to latch said units in active positions, and said control member having a second position in which it is engaged and operated by said pattern means to release said latch means from said units for return to inactive positions.

References Cited in the file of this patent UNITED STATES PATENTS,

2,100,345 Miller Nov. 30, 1937 2,432,110 Tambach Dec. 9, 1947 2,602,313 Reading July 8, 1952 2,746,275 Colbert May 22, 1956