US2588473A

US2588473A - Knitting machine

Info

Publication number: US2588473A
Application number: US127689A
Authority: US
Inventors: Belford Alexander
Original assignee: Scott and Williams Inc
Current assignee: Scott and Williams Inc
Priority date: 1949-11-16
Filing date: 1949-11-16
Publication date: 1952-03-11
Anticipated expiration: 1969-03-11

Description

March 11 1952 A. BELFORD 2,588,473

KNITTING MACHINE Filed Nov. 16. 1949 3 Sheets-Sheet 1 10 H W H 14 x 1 -lHlk- 1B INVENTOR. l ALEXANDER BELFORD BY I @(VY Y @7 ATTORNEY March 11, 1952 Filed Nov.

A- BELFORD KNITTING MACHINE 3 Sheets-Sheet 2 INVENTOR. ALEXANDER BELFORD aw Y Q I ATTORNE S.

March 11, 1952 BELFORD 2,588,473

KNITTING MACHINE Filed New. 16, 1949 5 Sheets-Sheet 3 INVENTOR. ALEXANDER BELFORD ATTORNEY Patented Mar. 11, 1952 UN I'TED STAT ES O F 2,588,473

KNITTING MACHINE Alexander Belford', Laconia, N Hg, a's's'igiibr to Scott & Williams, Incorporated; Eac'onia; N: H., acorporation of Massachusetts Application November 16, 1949, Serial-No. 127,689

Claims.

This invention relates to knitting. machines and in particular has reference to the control of wrap yarns to. secure proper plating of a main yarn or yarns.

Considerable difliculty has been encountered when attempting to plate one or more main yarns with wrap yarns fed to groups. of selected needles dueto the factthat satisfactory control of the relationship of the wrap and main yarns could not be maintained. So-called plating cams. have been provided toimprove the plating. by exerting a degree of control but these plating cams. have not exerted sufficient control to insure proper plating under conditions ofvariations in the selection of groups of needles being wrapped.

The broad object of the present invention may be stated to be the provision of control means to secure proper plating by wrap yarns. In accordance with the invention there is provided a special type of plating cam bearing, in particular, proper relationship to a stitch cam and sinkers and having a controlling edge properly contouredv to efiect-desired control. Additionally, in accordance with the invention special sinkers are provided which cooperate with the plating cam and; in particular, permit it to depressthe wrap yarn to proper extents and positions forsecuring. most effective plating.

Further, in accordancewith the invention,.it. is possible to-wrap with a-heavy wrap yarn more needles thanhas been heretofore possible, this end being achieved by quick reliefoi' strain. on leadingstitches of a wrapped panel after their formation.

Subsidiary objects of the invention relate to these and other details of construction. and'operation and will become apparent from the'folflowing description read in conjunctionwiththe accompanying drawings in which:

Figure 1 is a fragmentary view partlyin sec tion looking radially outwardly of the. needle cylinder at those parts of the machine which are particularly concerned with the operation of plating bya wrap yarn;

Figure 2 is a fragmentary" radialsection showing the relationships existing in Figure 1 be tween the last needle to take a wrap yarnin' a course, an associated sinker and the associated plating cam;

Figure 3 is a view similar to Figure 1 but showing a later event, the wrap yarnhavingbeen drawn onto the platform of a sinker adjacent to the last needle wrapped'in the course; and

Figure 4 is a view similar toFigureZshowihg the'relationships existing in Figure 3;

2. Inasmuch as the invention is applicable to cular knittingmachinesiii general and concerns only particular pa'r't's-of'sucli machine), thereare illustrated and described only those parts" which" are directly concerned with the present invention. As an example'of the type" of machirie'te which the' invention applicable" there ma'yfbe' referred" to the patent to I. W; .Grothe'y" No; 2,138,738; dated November 29,1938, which; inpar' ticular, in Figures 2"and"3"illustrates the mount?- ing and arrangement of a plating dam of l the" general'type referred to above.

Lat'chneedles" 2' independently mountediiisldts" in" a conventional'needle'cylinder (not"illustr"ated)' are provided with butts 4 which areac'ted upon" by cams including a stitch ca'r'ri ahavin'g'anedge" 6 for engagingfthebutts' andm'oving the needles" downwardly in" the stitch drawing operation. This stitehcam is generallycoriventional but'its" edge 6 may be somewhat steeper than" usual, for? l which is'als'o' steep ('e. g. 48") whicl'i'is lficate'd above an edge 9 of a relief cam,.whicl1"edge' also steep; for example; havingant'aiigle'of about" 47with'the horizontal. As'will appear "from the discussion hereafter a steep angleon the" stitch cam? while" desirable has heretofore hadan objection" use when wrapping. was involved: In acc'o'rdance' with the present invention" a" steep stitch; cam may be used with no objectionable" Further more detailed" reference to? the" results. relief cam will b'emadeiater;

On'eor m'orem'ain yarns are fed fromcorrespo'nding'feeding fingers" and in the presentcase' one such" feeding finger is indicated at 10; this needles from thethro'at l2 o'fthelatch ring I 4."

The platingcam' IB located during plating" operations in the position illustrated i'n' the figures and-may be-mounted in the same fashionas' the' plating carr'lillustrated in theGro'they pat ent referredto above: Accordingly; the mounifhas. thesame' slope'as' the e'dgeii ofthe' stitch cam. At it's 'lower" endtheportion-H merges the" cam which" is continued? as a" further are. at 282" As will hereafter appear these various poi-- tions of" the cam edge have" individual" andii'n'r DOrtant' functions:

The various wrap yarns are fed from individual wrap fingers and one yarn W and its corresponding wrap finger 3D is illustrated. The wrapping may be carried out in any of the conventional fashions used for panel wrapping. For example, the method of wrapping may be that of the Grothey patent. In brief, in any such wrapping operation a wrap finger is normally located inside the needle circle and when wrapping is to occur it is projected outside the needle circle and then by one of various alternative means the wrap yarn is caused to be delayed relative to the moving needles so that the wrap yarn is laid below the hooks and above the latches of those needles which are to be wrapped. Selection to secure various patterns is generally accomplished by the selective projection of the needles in position to take the wrap yarn, those needles which are not to take the yarn remaining low so as to miss it. Alternatively, the

needles which are not to take the wrap yarn may beprojected to an unusually elevated position so that the wrap yarn will be placed on them below their latches and will not be entrapped in the hooks during yarn drawing operations. If the former procedure is adopted and intermediate needles of a group are not to be wrapped while end needles of a group are to be wrapped, the needles of the group which are not to be wrapped will eventually ride along with the Wrapped needles and in attaining such position they will rise outside the wrap yarn extending between needles which are wrapped. This is designated as interlacing and such interlacing is illustrated in Figure 1 in which the

needles

2A and 2D are wrapped while the

intermediate needles

2B and 2C are not wrapped, these needles in Figure 1 being located with their upper ends outside the wrap yarn extending between the

needles

2A and 2D. As illustrated the needle 2A is the last of the needles to be wrapped in the course which is being formed. 2D may be either the first needle of a group which is wrapped or may be one of several of the first needles of the group which are wrapped. It may be here noted that the wrap yarn will extend from the last needle to be wrapped in the preceding or some earlier course in the fabric F to the first needle of the group under consideration. The portion of the wrap. yarn thus extending from a preceding course must also be properly controlled as will be described in more detail hereafter.

Sinkers. 32 are mounted between the needles and have a wave imparted thereto in.the usual fashion. The ledges of the sinkers over which theyarns are drawn are indicated at 34. In some cases it is desirable that the sinkers when moved inwardly should aid in moving the fabric F inwardly and for this purpose some of the sinkers are provided with rounded teeth indicated at 36. A usual set-up of sinkers involves the alternation of such toothed sinkers with plain sinkers,' the inner ends of which have smooth and rounded upper edges as continuations of the ledges 34. When the action of sinkers on the fabric is not required all of the sinkers may be of the smooth variety. In accordance with the present invention there is located inwardly of the ledge 34 a depression in the form of a notch 38 which is aligned directly below the plating cam I6 when the sinkers are in the positions which they attain at the time stitches are drawn. At this time the notches or depressions 38 are located immediately inwardly of the backs of the needles as indicated in 4 Figures 2 and 4, the sinker ledge 34 terminating inwardly approximately at the radius of the backs of the needles.

The parts entering into the control of the yarns having now been described, there may be discussed the functions and operations of these parts.

It has been recognized that a wrap yarn could be more positively plated over a main yarn or yarns if the needles could be passed down the stitch cam more rapidly than usual and to do this and still maintain a proper path the usual practice would have been to make the operating edge of the stitch cam somewhat concave so that the downward rate of movement of the needles would be accelerated as they passed down the stitchcam. However, due to the fact that the underside of the plating cam was shaped as an are, as illustrated in said Grothey patent, which would amount to its having a shape, referring to the present drawings involving a continuation of the edge I8 convexly down to its lowermost portion 25, the wrap yarn would have been held so low on the cheek of the last needle to be wrapped that as the latch of this needle was closed by the stitch held on the needle the wrap yarn would have been trapped and broken fibers, spoiling the appearance of the fabric, would have resulted. The slope of the stitch cam accordingly was limited by consideration of the fact that the wrap yarn had to be held sufiiciently high to prevent entrapment.

In accordance with the present invention the initially active portion l8 of the edge of the plating cam, which portion of the edge acts in the usual fashion to control the position of the wrap yarn during initial movement of the needles by the stitch cam, is followed by a substantially horizontal portion 20 and then by a further sloping portion 22. The result is that the lowering of the wrap yarn by the plating cam is momentarily interrupted so that when it is again moved downwardly by th plating cam it will be located relatively high in the needle hooks. To achieve proper results the operating angle of the stitch cam is stee ened, for example to about 47, in effeet by advancing the bottom of the stitch forming edge to the right but without changing the relationship of the contact point of the needle butt with the stitch cam edge with respect to the main yarn feed. The edge portion 22 of the plating cam is at the same angle as the active edge of the stitch cam with the result that the wrap yarn is caused to move at the point where it engages the last needle which is wrapped in a path nearly parallel with the path of the main yarn and with the path of the upper ends of the needles. Accordingly, the relationships of the wrap and main yarns to each other and to the needle hook are maintained substantially constant from the time the wrap yarn engages the portion 22 of the plating cam until the yarns engage the sinker ledges. This maintenance of relative positions insures a proper plating relar tionship at the time the needle hook starts to draw the main and wrap yarns through the previously formed loop.

For proper plating the wrap yarn must be held in the back of the needlehook when it is drawn over the sinker platform or ledge 34. The bottom 26 of the plating cam should be low enough so that the wrap yarn would extend horizontally from beneath the plating cam to its position in the hook. In past arrangements the plating cam could not be set low enough to insure such a direction of feed due. to the fact that thewrap yam aswell as the previously formed fabricwassupported by the horizontal. conventional .sinker ledge to a point extending inwardly under and beyond the plating cam. To insure the possibility of a sufliciently low position. of the plating cam, the depressions or notches 38 are provided in the toothed sinkers while a corresponding clearance is'provided in the conventional sinkers Without teeth by shortening the ledges or platforms so that when in the position illustrated the ledges or platforms will not extend inwardly of the backs of the needles. The depressions or clearances thus provided in all of the sinkers allow the plating cam to be set. sufficiently low for positive plating but provide a space into which the previously formed fabric and the wrap yarn may be depressed. This avoids the production of rubbing friction which would tend to produce fuzzing of the yarns. tion 28 of the plating cam beyond its lowermost portion 26 as an arc of substantial radius is also important. Considering the first needle of a group to be wrapped the wrap yarn will extend to this needle from the wrapped stitch of the fabric in which it was previously knitted, around this needle and thence possibly on the outside of additional needles which are to be wrapped and on the inside of interlacing needles which are not to be wrapped. Tension is applied to the wrap yarn by means of a conventional spring take-up which is not shown herein and, since the yarn extends upwardly from the first needle to be wrapped as that needle approaches the yarn drawing point, it will be evident that the applied tension may cause the wrap yarn to be located so far up in the needle hook as to be clamped on top of the main yarn and thus produce an improperly plated stitch. The portion of the wrap yarn extending from the last needle wrapped to the wrap finger will be cammed downwardly by the plating cam but must not be suddenly released for possible upward movement immediately after it passes the lowest point of the plating cam. The large radius at 28 will serve to hold this portion of the yarn downwardly even beyond the lowermost point of the plating cam to insure that it will maintain its proper relationship to the main yarn or yarns until the stitch is sufficiently drawn so that it cannot thereafter get out of its proper relative position.

It may be noted that the lowermost point of the plating cam is, as illustrated in Figures 1 and 3, at that point where the drawing of the yarns for new loops commences.

As a result of the foregoing the plating cam assumes and maintains control of the wrap yarn to insure continuously, so long as a possibility of change of relative positions could occur, the proper relationship of the wrap yarn to the main yarn or yarns and to the hooks of the needles.

In order to give wrapped stitches more prominence it is often desirable to use a wrap yarn heavier than that from which the main fabric is knit, and when several consecutive needles are wrapped with such a wrap yarn the result is an exceptionally heavy fabric over a local area. In the past, it has not generally been practical to wrap more than three consecutive needles with a single heavy yarn and even this has been possible only due to the fact that "robbing of yarn occurs. In the present instance, as illustrated in Figure 1, the lower point of the stitch cam 8 is followed almost immediately by the The formation of the porrise 9. oft the relief cam, which rise occurs at a steep angle so that the needles, after drawing their stitches, are raised suificiently quickly to 1. In a: circular knitting machine, independent needles and sinkers, means for feeding a main yarn to the needles, means for feeding a wrapv yarn to a group of needles in a single course, cam means for moving needles-in a predetermined path for the seizure of the main yarn, andaplating cam locatedinside the needle circle and engageable with the wrap yarnat a part thereof be tween the last needle of a group to be wrapped and the wrap yarn supply. said sinkers having ledges over which stitches are drawn and provided with clearances inwardly of the ledges and adjacent to the plating cam when positioned at the circumferential position of closest approach of the plating cam to the sinkers, so that the wrap yarn may be located by the plating cam to extend therefrom towards a needle approximately parallel to the plane of the sinker ledges.

2. In a circular knitting machine, independent needles and sinkers, means for feeding a main yarn to the needles, means for feeding a wrap yarn to a group of needles in a single course, cam means for moving needles in a predetermined path for the seizure of the main yarn, and a plating cam located inside the needle circle and engageable with the wrap yarn at a part thereof between the last needle of a group to be wrapped and the wrap yarn supply, said sinkers having ledges over which stitches are drawn and provided with clearances inwardly of the ledges and adjacent to the plating cam when positioned at the circumferential position of closest approach of the plating cam to the sinkers, so that the plating cam may press previously knitted fabric beyond the level of the sinker ledges.

3. In a circular knitting machine, independent needles and sinkers, means for feeding a main yarn to the needles, means for feeding a wrap yarn to a group of needles in a single course, cam means for moving needles in a predetermined path for the seizure of the main yarn, and a plating cam located inside the needle circle and engageable with the wrap yarn at a part thereof between the last needle of a group to be wrapped and the wrap yarn supply, said sinkers having ledges over which stitches are drawn and provided with clearances inwardly of the ledges and adjacent to the plating cam when positioned at the circumferential position of closest approach of the plating cam to the sinkers, so that the wrap yarn may be located by the plating cam to extend therefrom towards a needle approximately parallel to the plane of the sinker ledges, at least some of said sinkers being provided with teeth for moving inwardly previously knitted fabric.

4. In a circular knitting machine, independent needles and sinkers, means for feeding a main yarn to the needles, means for feeding a wrap yarn to a group of needles in a single course, cam means for moving needles in a predetermined path for the seizure of the main yarn, and a plating cam located inside the needle circle and engageable with the wrap yarn at a part thereof between the last needle of a group to be wrapped and the wrap yarn supply, said sinkers having ledges over which stitches are drawn and provided with clearances inwardly of the ledges and adjacent to the plating cam when positioned at the circumferential position of closest approach of the plating cam to the sinkers, so that the plating cam may press previously knitted fabric beyond the level of the sinker ledges, at least some of said sinkers being provided with teeth for. moving inwardly previously knitted fabric.

5. In a circular knitting machine, independent needles and sinkers, means for feeding a main yarn to the needles, means for feeding a wrap yarn to a group of needles in a single course, a steep stitch cam for moving needles in a predetermined path for the seizure of the main yarn, a plating cam located inside the needle circle and engageable with the wrap yarn at a part thereof between the last needle of a group to be wrapped and the wrap yarn supply, said plating, cam having an extended portion thereof engageable with the wrap yarn approximately parallel to said predetermined path of the needles, said stitch cam having a fiat bottom portion for maintaining the level of the needles for a short portion of their path of movement. and cam means for steeply reversing the movements of needles immediately following their release by said fiat bottom portion of the stitch cam, thereby to relieve tension on drawn stitches.

ALEXANDER BELFORD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,200,140 Robinson Oct. 3, 1916 1,214,828 Robinson Feb. 6, 1917 2,138,738 Grothey Nov. 29, 1938 2,263,492 Grothey Nov. 18, 1941 2,555,870 Bristow June 5, 1951