US3188835A - Thread clamping device - Google Patents

Description

June 15, 1965 Filed March 6, 1961 w. MAYER ETAL 3,188,835

THREAD CLAMPING DEVICE 2 Sheets-Sheet 1 2 i HIM I F I -L. 1a

6" WERNER- MAYER EWALD HANEL ATTORN June 15, 1965 w. MAYER ETAL 3,

THREAD CLAMPING DEVICE Filed March 6, 1961 2 Sheets-Sheet 2 WERNER M,4 YER [WALD HANEL BYBLLLT 55 D -King)? 5p! ATTORN 5 3 Claims. (:1. 66-145) The present invention relates to a thread clamping device, and more particularly to a combined suction and clamping device for securing thread during knitting operations in circular knitting and straight bar knitting machines.

Various thread clamping devices are known, which are generally used in connection with mechanical or electrical cutting devices for separating the threads from the articles being knitted at the end of a course of knitting (see. US Patents 2,908,154 and 2,924,958). The cutting device is normally placed at a point in the thread path between the article being knitted and the clamp device which serves to hold the thread end after cutting. The clamping device is positioned in the vicinity of the thread guide or feed means at the point in the knitting where the clamping and cutting is to take place. In particular, circular knitting machines cannot readily accommodate clamping and cutting devices for the knitting thread or yarn since such knitting machines are provided with cylinders of comparatively small diameters wherein several knitting systems or stations are utilized for producing, for example, fine seamless hose. Moreover, it will be appreciated that in the usual straight bar I knitting machines, space for accommodating said clamping and cutting devices is very limited as well (see US. Patents 2,844,016 and 2,863,310).

It is conventional to provide a suction pipe or nozzle for drawing 01f the thread ends by suitable suction upon the cutting of the thread at the end of a course of knitting. The suction pipe is generally positioned between the cutting device and the clamping device. Nevertheless, because of the relatively small distance between the suction pipe nozzle and the cutting device, Which ismade necessary by the lack of sufiicient space in the machine, the resulting thread ends upon cutting of the same by the cutting device are so short and stiiI that they cannot be readily retained with any degree of efiiciency by the air current generated by the suction pipe. Additionally, as is the case where electrical cutting or separating means are employed, such as for the cutting of synthetic or thermoplastic thread or yarn, the heating element, i.e. an electrical resistance Wire, is strongly cooled due to the continuous air current of the suction pipe positioned so closely thereto. Naturally, the greatest cooling effect is noticed at the outermost portion of the heated resistance Wire or element, which in any case is much harder to keep heated to the desired temperature than would be the remainder of the electrically heated resistance wire or electrical separator means.

It is an object of the present invention to overcome the foregoing drawbacks and to provide an apparatus for the efiicient, clamping of the thread used in circular knitting and straight bar knitting machines, such device being utilizable together with a cutting device.

Other and further objects of the invention will become apparent from a study of the within specification and accompanying drawings in which,

FIGURE 1 is a schematic partial perspective view of a portion of a circular knitting machine of conventional design illustrating the position relationship of the thread 1 United States Patent 3,188,835 Patented June 15, 1965 guide, cutting element, and thread clamping device of the invention,

FIGURE 2 illustrates schematically a partial perspective view of a straight bar knitting machine of conventional design provided with a cutting element, thread guide, and alternate embodiment of the thread clamping device of the invention,

FIGURE 3 illustrates a schematic partial sectional view of a thread clamping device in accordance with the invention similar to that shown in FIGURE 2 containing a modification for looping the thread retained by the device of the invention,

FIGURE 4 illustrates a schematic partial sectional view of the top portion of the thread clamping device of the invention 'as illustrated in FIGURE 3, and

FIGURES 5 and 6 are further schematic perspective views illustrating the withdrawing and inserting of the thread guide out of and into active feeding position.

In accordance with the present invention, it has been found that a thread clamping device for securing thread ends during knitting operations in circular knitting and straight bar knitting machines may be provided which comprises suction nozzle means and thread engaging surface means arranged in the path of the knitting thread for relative movement from a position out of thread clamping contact to a position into thread clamping contact with one anotherj The suction nozzle means preferablyincludes, in .accordance with one embodiment of the invention, used in connection with a circular knitting machine of the dial type, a tubular suction nozzle member positioned in spaced relation to and completely out of contact with the dial cap and a tubular extension member, such members being concentrically positioned for telescopic movement with respect to one another. In this manner, the extension member may be extended into and Withdrawn out of clamping contact with the surface means. Conveniently, the extension member outwardly encloses and is axially slidably upon the nozzle member, and the extension memher is preferably provided with an elastic end rim for engaging thread when such rim is extended into clamping contact with the surface means. The extension member, for efiicient operation, is normally resiliently urged into extended position for suitable thread clamping contact. The urging may be effected by means of a loaded coil spring disposed about the nozzle member and secured thereto at one end, the other end of the spring abutting the extension member for forcing the same into thread clamping contact with the surface means.

To actuate the extension member, for axial movement into and out of thread clamping contact, a draw rod may be connected to the extension member at one end and coupled with a suitable pattern device at the other end which causes the desired actuation to take place during the knitting operation.

A suitable pattern device, for example, may take the form of a guide cam ring concentrically disposed with respect to the cylinder, as will be more fully appreciated from copending US. application Serial No. 42,355, filed July 12, 1960, wherein a contact ring or guide cam ring for the control of thread guides is mounted for limited rotational movement in response to a cam drum or pattern drum linkage, such as that shown in British Patent No. 810,225. With respect to the instant case, such guide cam ring may be provided with an upper cam surface thereon which is followed by a follower portion of the draw-rod. Upon suitable actuation of the guide cam ring, the draw-rod will be axially displaced for movement of the extension member into and out of clamping contact With the surface means. If desired, the pattern device may be provided for axially displacing the drawrod once during each cylinder rotation, as for example a clamping.

would be the casein the knitting of a reinforcement thread into a reinforcement portion ofthe hose or tubular fabric article being knitted. One construction of actuation meansfor axially displacing the draw-rod once for each cylinder. revolution .-is described in detail in copending;U.S. application filed simultaneouslyherewith, it Serial No .93,804, filed'Mareh 6, 1961, entitled Thread Changing Apparatus Of course, the pattern device in-,

steadmay includea'simple pattern drum .which rotates at the same rate as the circular knitting machine, in connection with which the device may be used, such that clamping contact will be made once during each cylinder Various control cam devices of the forea y revolution. going type are well known and are indicated, for example, in U.S. Patent No. 2,908,154 and British Patent No. 810,225., p j

On the other hand, where used with a straight bar knitting-machine, a suitable timing device may actuate the clamping means into and out of clamping engagement as for example when the yarn or thread being knitted is removed from knitting action at the end of the last vknitting course to be knitted therewith, such as where the thread guide reaches the end of the needle bed. The

I for cutting the thread for example after threadclamping contact .has been achieved between thesuction nozzle means and the thread engaging surface means:

Where the thread clamping device is used in connection with a circular knitting machine, the thread engaging t a 4 i As is specifically the case with straight bar knitting machines of conventional design having ,a bed of knitting elements, the suction nozzle means may be stationarily positioned at the end of'the bed with a' thread cutting element disposed-adjacent the cover surface between the end of the bed and the suction nozzle means. Suitably; the cutting element andcoversurface'are mounted on a' shaft for movement. across the path of'the thread" to be clamped. f These elements are aligned atv the end of the bed so that they will be first: actuated away from the thread path before the thread guide carrying the thread therealong passes'to inactiveknitting position.

back across the thread path. .Since the cover surface is positioned more forward than the cutting" element,'the cover surface will engage the thread and move'the same intothread clamping contactwith the suction nozzle means before .the thread will be cut by the cutting element. i V 7 An. electrical resistance wire heating element of conventional design is normally'used for effecting the cutting of the-thread after clamping has been achieved. (See U.S.- Patents 2,844,016 and 2,863,310.)

It is apparent therefore that in accordance with the present invention, the clamping of the thread 'is carried out. by the opening or rim end of the suction nozzle means together witha thread engaging surface means movable into thread clampingrelationtherewith, Be-

cause of the advantageous covering over of the suction nozzle means during clamping, no cooling air current i will flow which would-otherwise.undesirably cool the electrical resistance wire cutting element. Not. only is 'the avoidance of unnecessary cooling ofthe electrical cutting element attained but also a saving in thegensurface means is conveniently definedby the top surface ofthe stationary dial cap so that clamping contact is effected by moving the extension member from withdrawn or opened position into contact with the top surface of such'dial cap, i.e. to closed position. In this con nection, a thread cutting elment is preferablypositioned on the dial cap and the thread guide is positioned adjacent the dial cap at the point where thread cutting is to take place. The tubular extension member is thus positioned between the thread guide and cutting element for extension into clamping contact with the dial cap. This occurs where the path of the thread being knitted by the machine 'is situated intermediate the withdrawn tubular extension member and the dial cap so as to permit the'desired Alternatively, and especially where the device of the invention is used in connection with straight bar knitting machines, the thread engaging surface means is defined asa cover surface adapted t o seal off the; suction nozzle means when thread clamping contact is achieved.

eration of suction through the nozzle means passage. Moreover, the interruption of. the suction air current during thread clamping contact may result in the need for less expensive suction equipment or the application of present'equi'pment for a greater numberof suction nozzle means.' .7

The elastic material suitablyprovided on at'least one of the thread clamping members for engaging the thread to be clamped, may be inthe form of rubber, resilient or-soft synthetic, plastic, or other resilient or soft material permittmg-asure grasp of the thread and a suitable sealing ofl? of the air curren-t passing through the suction nozzle means. a

Naturally,.where the thread engaging projection means insertable within the suction nozzle rneans is present, long thread ends maybe retained by the suction nozzle means f of the thread clamping device even where the operative elements have been withdrawn from .thread clamping this instance, the suction nozzle'means need not'be provided with a tubular extension, but instead contact is achieved by pivotal movement of the cover surface into clamping engagement with the .end rim oredge ofthe suction nozzle means. Suitably, the cover surface is provided with an elastic portion disposed thereon for achieving sealing engagement with the suction nozzle means while clamping thread therebetween; V

In accordance with a preferred modification of the invention, the cover'surface is provided with a thread en-' knitting machines.

' contact. Because a long thread end is present ,as compared'with the diameter of theopening of the nozzle 7 means, the thread'end will be reliably held by suotion when clamping contact ceases.

'Advantageously, this feature 1s provided even though the thread separator or electrical resistance wire cutting means, is relatively closely positioned. to the thread-clamping means of the invention as is particularly the case 'with straight bar It willbe particularly appreciated that the present invention represents an-improvement in circular knitting machines having means for forming knitted pattern areas in Va 'tubular. fabric,'-for example, such machine including a needle cylinder, needles disposed in said cylinder,

gaging projection means insertable into the suctionjnozzle means, passage duringv the threadrclampingcontact. The projection meansis adapted toengage the thread-to be clamped, and in this manner carry a portion thereof into. the suction nozzle meansv passage upon the thread clarnpingcontact so' as toform a loop portion in the thread. 7 a

elements cooperating with the needleslfor formationof stitches,-ca-msforfefiecting needle. movement, yarn feedmg or guide means movable from an active yarnfeeding position whereinyarn is fed to the needles for 'knitting jthereby to an inactive yarn feeding position --,wherein the yarn,1s in non-knitting p0si-tion,- and means for clamping and cuttingi the yarn when the yarn feeding means is in active yarn feeding position and forreleasing the yarn when the yarn feeding means is moved to active Once the thread or yarn hasipassed, the 'shaftis next actuated yarn feeding position. The improvement of the invention generally comprises a combined thread clamping and suction device including suction nozzle means and thread engaging surface means which are arranged for relative movement from a position out of thread clamping contact to a position into thread clamping contact with respect to one another when the yarn feeding means or thread guide is in active yarn feeding position. The thread clamping device of the invention, of course, is readily usable together with a closely positioned thread separating or cutting device, since the improvement of the invention is directed to the more efficient clamping and cut-ting of thread in relatively confined spaces than could be achieved heretofore.

With respect to the drawings, FIGURE 1 shows a portion of a conventional circular knitting machine having a cylinder rotating in the direction of the arrow P, said cylinder being provided with a needle bed having a plurality of needles N axially disposed in slots therein in the conventional manner.

As is customary in circular knitting machines for the production of seamless fine hose, the cylinder is provided with the normal dial 6' for the slidable reception of the transfer bits (one of which is schematically shown at 6"), dial 6' being positioned over the top end of the cylinder. Disposed above the dial 6 is a dial cap 6 which is stationary. Dial cap 6 is provided with a thread separator 5 which may be an electrical resistance wire doubled back on itself to form a vertical heating element maintained at a temperature suflicient to sever the particular yarn or thread used, i.e. nylon, etc.

Disposed immediately above dial cap 6 in spaced relation thereto and completely out of contact therewith is tubular suction member 1 connected with a vacuum or other source of suction remote from the circular knitting machine. Extension piece 2 is telescopically slidable on suction nozzle member 1 and is normally urged in downward direction by coil spring 3 attached at its upper end to suction nozzle 1 by means of a collar 4 and positioned in urging abut-ment with the top edge of extension piece 2. Extension piece 2 is suitably provided along its lower edge or rim portion with an elastic covering 21 made of rubber, for example, which forms the surface against which the thread P will be secured. Draw rod 7 controls the axial movement of extension piece 2 with respect to suction nozzle 1 so that the extension piece 2 may be urged by spring 3 into thread clamping engagement with the top surface of stationary dial cap 6. Drawrod 7 may be suitably connected with a pattern device such as a pattern drum D rotating at the same rate as the cylinder or any other control means as aforesaid so as to cause displacement of draw-rod 7, as for example, once during each rotation of the cylinder.

In this way, where the needles are suitably actuated in the usual way, by cam means within a certain portion .of the circumference of the cylinder as may be the case, for example, in adding a reinforcement thread or yarn to be knitted along only a portion of the knitted article, such as is the case with rein-forced soles and heels of fine hose, the thread guide or thread feeding means 8 may be lowered into active position immediately adjacent the needles N in any suitable manner, such as by rotating cam E or .by the afore-described means set forth in said co-pending US. application Serial No. 42,355. The

first needle of that portion of the cylinder needles to be actuated, as by suitable activating cam means, for the knitting of the reinforcement portion of the hose, therefore, will be raised into the path of thread F since thread guide 8 has been downwardly displaced into active knitting feed position across the needle path. The thread Fmay now be knitted in the normal manner until the knitting course recahes the last needle of that portion of the needles of the cylinder used to knit the reinforcement portion of the hose. When this occurs, thread guide 8 will be suitably upwardly displaced out of active thread feeding position by suitable control means as aforesaid, whereupon the last needle N of the said portion will remain in engagement with the thread F and carry the same in the direction of the arrow P around the cylinder therewith. When the last needle N passes a certain point, the thread P will be disposed along dial cap 6 directly beneath extension piece 2, extension piece 2 having been upwardly displaced in the meanwhile to permit the thread F to pass directly therebeneath, for example at about the same time that thread guide 8 is upwardly displaced out of active knitting position. Then, extension piece 2 is once more downwardly urged into thread clamping contact with dial cap 6 retaining the thread F securely. At this time, as the said last needle N passes around the cylinder circumference, the thread will abut the then electrically energized thread separator 5 whereupon the thread will be severed leaving only a small end in the reinforcement portion of the hose being knitted, yet leaving a suitably long end portion of the thread F which will be effectively retained by the thread clamping means and especially by extension piece 2, even after the same is next raised from thread clamping contact, due to the suction provided upon raising.

It will be appreciated that during knitting operations, normally extension piece 2 will remain in abutment with dial cap 6 to prevent the undesired passage of suction air current upwardly through extension piece 2 and suction nozzle member 1. The undesired cooling of electrical resistance wire heating element 5 will, therefore, be prevented.

Thus, where the first needle of the needles to be used for knitting the reinforcement portion of the hose comes into engagement with the activating cam means therefor, which may be stationarily positioned while the cylinder containing the needles rotates therepast, suitable preselected needle butts on these needles will be urged by the cam means in upward direction just after the thread guide 8 has been downwardly displaced. Stated another way, the thread guide 8 will have been switched to activated position just prior to the passage of the first reinforcement needle therepast. The extension piece 2 remains in clamping engagement with dial cap 6 during this time. Of course, suit-able pattern devices may be used to control the timing of the lowering and raising of thread guide 8 into and out of active knitting position which may be carried out in accordance with the aforesaid cam ring displacement arrangement disclosed in said co-pending U.S. application Serial No. 42,355.

Specifically, a pattern drum may be opera-tively connected by suitable linkage means to actuate cam ring means for lowering and raising thread guide 8, which drum revolves in dependence upon the rate of revolution of the knitting cylinder or independent thereof as the case may be. Consequently, thread guide 8 will be inserted into active feeding position across the knitting needle path before the first needle to be employed for knitting the particular yarn or thread passes that point. This first needle, as aforesaid, may be the first needle of that portion of the needles along the cylinder circumference used for knitting the reinforcement portion of the hose.

In accordance with the preferred operation of the invention, the first needle of said portion of needles will be actuated for knitting by the cam means directly adjacent the position of thread guide 3, while the thread end extending therefrom to the extension piece 2 will be carried along by said first needle to a point adjacent the location of thread separator 5, whereby severing of this thread end will occur close to the first stitch. In this manner, the thread end held by the thread clamping device will be brought into contact with thread separator 5 cutting off such thread end and allowing the same to be retained by suction nozzle member 1 until extension piece 2 is next raised. The other end of the thread in the course being knitted will be desirably short in length so that a minimum of thread ends will occur in the knitting of the reinforce-z.

ment portion. I

In turn, when the last'needle passes thread guide in V the direction of the arrow P, the control of thread guide 8 is such that the same will be upwardly displaced out of active feeding position. Nevertheless, the last knitting needle will carry the thread F along the path of movement of such needle a certain dist-ance whereupon 'a similar counter-clockwise, as viewed inthe drawing, cover plate 12 will 'clam'pingly engage thread E against the nozzle a rim of suctionnozzle means '1 before separator-element 5' comes into contact with the thread. I I I A suitable control mechanism may be provided which may be timed to be actuated, to pivot shaft 13 in the pat-tern device such as a pattern drum will have caused draw rod 7 to be upwardly displaced also displacing extending piece 2. The already cut thread end will now pass through nozzle member 1. The thread F will pass di- 7 rectly beneath extension piece 2 as it is carried by the'last needletow-ard thread separator 5.- Aftera suitable move- I I ment of upwarddisplacement, extension piece 2 Will have i been once again downwardly urged bydr'aw-rod 7 in consequence of the control means used, ie a pattern drum or the like. ,The thread continuesv to move with'the I last needle until the same abuts the thread cutter or be readily retained by 2 even'when said extension piece is next raised, due to the air, suction through suction nozzle member 1.

Of course, alternatively, extension piece 2 may be kept in raised position untilafiter thread F has been'severed by separator 5 so that the thread end extending from extended position of member 2 into contact with dial 'cap 6..

Normally, extension piece 2 is'raised once during each placed 'in'engag'ement with nozzle meansl' to tseal of]? desired forward direction "as shown the arrows just after thread guide 8' whichis being withdrawn from active knitting'position has passed the nozzle 1' along thercourse of movementthereof with respect to the sinker head 14. Naturally, it;is preferred to resiliently mount lever 9 on shaft 13 so that upon contact between the 'nozzlerim of suction nozzle 1' and coverplate 12, shaft 13 may be. turned even further'acertain increment to allow thread separator 5" to comeginto contact with the thread F. 'Upon the'return movement of thread' guide 8"back into active knittin'glpos'ition, a suitable control inay-urg'e shaft 13 in reverse direction so as to withdraw cover plate 12 and separator element 5 from the path of thread F. Nevertheless, cover plate 12 may be again suction by forward movement ofgshaft I3 a certain increment so that thread guide 8' may proceed with the further knitting in opposite direction without the'thread ;30 thread guide 8 will be drawn by suction into nozzle mern-:. her 1 and retained thereatin raised positlon as well as in revolution of the cylinder since this is only needed to permi t the thread to be clamped at theend of theknltting of I 1 I a course of the reinforcement portionof thehose, Even so, the extension piece 2 may be raised after the start of a the knitting of the next level or course of stitches of the reinforcement portion upon the severing of the portlon of thread held by the clamping meansfrom the new thread to be knitted, so that the thread end severed by thread separator 5 may be withdrawn through suction nozzle 7 member 1. Of course, such removalmay await the aforesaid raising of extension piece 2 at the cuttingofthe thread at the end'of reinforcementportion whereby the being severed by separator element 5.; I I

If desired, once the knitting in the opposite direction has started, suitable further forward actuation of shaft 13 may occur due'to the resilient mounting of lever 9 upon shaft 13, so that separator element- 5' is once more brought'into contact with/the end'of thread F between the needle bar' and-the-nozzlemeans 1'. In this manner,

.only short thread ends. will remain along the edge of the fabric. 'When threadguide 8' completes a further knitting operatiomfit is once more passed in the return direction towards separator 5'. Shaft 13 may be suitably actuated to withdraw separator '5? and disengage cover plate" 12 from 'the'rim of nozzlemeans 1" whereby the passage of thread therealong is facilitated The cycle may then be repeated. i Specifically, in operation, for example, when the production of the double edge or turned welt portion, of the already cut piece may be withdrawn through. suction",

nozzle member 1 at that time.

With respect to-FIGURE 2,"a conventionalistraight bar knitting machine is shown having'a bed of needles N and a cooperating bed of sinkersS along the center bed 15. A thread guide 8' is, disposed in the conventional manner fo'r'passage along thev needles .and sinkers for the usual knitting procedure; At the end of the machine, when aparticular knitting operationhas been completed with respect to thread guide 8', the thread E is normally severed by a cutting or separating element 5'.

In accordance with the present invention a suction nozzle means 1' isdisposed'directlyadjacent the path of movement of the thread 'F carried'by thread guide. 8' along,

the course of the sinker head 14; In this instance, a lever 9 is disposed on a pivotable shaft '13, said lever-having a'cover plate 12 provided witha'suitable elastic cover- 7 ing 11 formed ofjrubber-or the like. Also disposed on I knitted article l as be'en completed, and another thread guideis'to beinsertedintoactivethread feeding position, a controlflinkage including a conventional pattern drum arrangement or other conventional means *(se e 'U.S.

Patents -2,844,016"and 2,863,310) may causej'the withdrawing of thread, guide 8 from active knitting position to -the inactivepositionshown in FIGURE 2. The thread guide 8 will remain 'in the inactive position shown in FIGURE 2 'until nextactuated' However, prior to the withdrawing of thread guide 8' to the position shown inFIGURE 2, shaft 13is rotated anincrer'nent in clockwise'directionso that cover plate 12 and separator element 5' will berearwardlyurged out shaft 13 is'the conventional cutting element 5', which may take theform of an electri cal-resistance element which is heated to a high enough'temperature to effect the severing of the thread or yar n F. While both lever j 9 and thread separator or cutting element 5' are disposed for movement on a'common shaft 13, cover plate"12 will' of ,thepath of "thread guide 8',to vthe position shown inFIGURE 2. When thread guide 8'* has reached in active position, shaft 13, may be forwardly rotated, so

that thethread F willbe cla'rnpedby cover plate 12 and nozzle means 1" will be sealed. Upon further forward (counterclockwise) rotation of shaft 13,"separator'eleme'nt 5' wi ll sever the thread F close to the fabric edge. Coverplate 12 will retain thethread end extending from :thread guide 8' thereto. When threadguide 8' is again to be placed inactive knitting position, shaft 13 again rotates in clockwise. direction; withdrawing cover plate 12 and separator element S'fromIthe thread path, and

allowing the previously severed thread end extending fromthread guide 8 to the nozzle means 1 to;be drawn be positioned with respect to said shaft at a point closer to the path of thread Fthan that of separator elements,

In this manner, uponfpivoting shaft 13 to the left or by suction into the nozzle rneans l. After thread guide '8? has passed thereby'an'd become engaged once more inactive knitting of thread E, shaft '13. may be conveniently rotated in counterclockwise direction again to cause the covering of nozzle'means 1 by cover plate 12 and thereafterthe f'severing of the thread between nozzle means '1' .andthe fabric edge byeIementS'. The severed end of thread held between nozzle means 1' and cover plate 12 will be drawn off by suction through nozzle means 1 the next time cover plate 12 is withdrawn from clamping contact. The cycle may then be repeated.

It will be appreciated that shaft 13 may be duly actuated in the desired sequence in dependence upon a control linkage to a pattern drum in the conventional manner (see US. Patents 2,844,016 and 2,863,310).

FIGURES 3 and 4 illustrate the modification wherein a thread engaging projection 16 comprising a wire loop having an inwardly directed arcuate portion is disposed on cover plate 12. Projection 16 will, therefore, engage the thread F by the inwardly arcuate portion and force the thread within nozzle means 1 when lever 9 is pivoted in forward direction with cover plate 12 being placed in clamping engagement with the nozzle end of nozzle means 1. A suitable length of the thread F will, therefore, be drawn so as to ensure a retention of the thread end even when cover plate 12 is withdrawn from clamping engagement with the end of nozzle means 1. It will be appreciated in this connection that by means of the projection 16, a sufliciently long piece of thread may be provided as desired, even though the suction nozzle means and thread clamping device of the invention are placed immediately adjacent the thread cutting or separator element 5' because of the restricted space for maintaining these working elements.

In accordance with the present invention, it will be appreciated that where desired cover plate 12 may be formed instead as a ring to permit clamping yet allow the passage of suction air into and through the nozzle opening.

To more clearly illustrate the preferred manner and sequence of Withdrawing and inserting the thread guide means from an inactive yarn feeding position where the yarn is in non-knitting position to an active yarn feeding position wherein the yarn is fed to the needles for knitting thereby, FIGURES 5 and 6 are included. These figures show the invention as applied to a circular knitting machine and indicates that the clamping means of the invention and the cutting means for the yarn or thread may advantageously both operate when the yarn feeding means or thread guide 8a is moved to inactive yarn feeding position, whereas when the thread guide 8a is moved to active yarn feeding position, the clamping means may remain closed while the cutting means alone will operate.

Accordingly, as shown in FIGURE 5, the cylinder needles N rotate with the cylinder in the direction of arrow P.- When the last needle which should take the yarn of the thread guide 8a, i.e. the reinforcement portion of the hose, for example, has passed thread guide 8a, a suitable control coupled with the rotation of the cylinder, for example such as a pattern drum, causes movement of thread guide 8a towards the center axis of the rotating cylinder of the circular knitting machine. At about the same time, draw-rod 7upwardly displaces extension piece 2 so that the last needle which engages a thread will carry the same therewith along the cylinder circumference in the direction of arrow P. This needle passes through positions N, N N N N The path of movement of the thread during this time is illustrated schematically in dotted line such that the thread will be disposed directly beneath extension piece 2 by the time the same comes into contact with the thread separator 5. Draw-rod 7 may now be suitably actuated to permit thread clamping engagement betwen stationary cover plate 6 and extension piece 2. Once the thread abuts separator 5, it will be severed leaving only a short thread end at the terminal edge of the reinforcement portion of the course being knitted. The other end will be suitably drawn by suction into extension piece 2 and retained by extension piece 2 and dial cap 6 until after the thread guide 8a has next been switched into active yarn feeding position and is again switched to inactive position. The cycle is then repeated, extension piece 2 being raised, the previously severed thread-end being drawn off by suction through nozzle member 1, the new thread once more passing directly beneath extension piece 2, extension piece 2 being lowered again and the thread again severed by separator 5 as indicated in FIG- URE 5.

The control of inward movement of thread guide 8a may be carried out by means of rod 8b operatively linked with a pattern drum as mentioned above such that with each revolution of needle N, thread guide Set will be inwardly displaced just as needle N travels therepast in the direction of arrow P. A similar pattern drum or other device may be used to lift extension piece 2 from normal engagement with cover plate 6 just as thread guide 8a is inwardly displaced, but in this case only until the thread passes directly therebetween whereupon extension piece 2 will be allowed to be lowered once again into clamping engagement.

Concerning FIGURE 6, the initial needle of that portion of needles on the cylinder used for the knitting of the reinforcement portion of the hose is designated needle N,,. This needle is actuated in the normal manner for knitting, but before the same has passed thread guide 80, suitable control by means of said pattern drum, for example, causes such thread guide 8:: to be outwardly displaced away from the center of the cylinder. The thread thus passes the path of needle N, whereupon the thread is carried with the initial needle in the direction of arrow P, executing the positions N N N N The position of the thread in this connection is schematically designated by dotted line. The free end of the thread during this movement is retained by extension piece 2 which is normally urgingly in engagement with cover plate 6. When the thread touches the separator element 5, the thread end is cut e.g. at the initial edge of the reinforcement portion of the hose such that this edge will have only very small thread ends due to the close positioning of the needles and the separator element. The knitting is carried out in the normal manner during this time. The separated end of thread will be simply drawn by suction into extension piece 2 and nozzle member 1 as soon as extension piece 2 is next raised. The actuation of rod 8b in reverse direction to displace thread guide outwardly with respect to the center of the cylinder as aforesaid is suitably controlled by the pattern drum. For example, this may operate at the same rate as the cylinder speed of rotation where a reinforcement thread is to be knitted alonga portion of each knitting course of the main thread, so that each cycle of the cylinder and the drum coincide for the desired control movements.

Of course, where the thread guide 8a and the extension piece 2 are assigned for use during the knitting of hose in the normal manner, the thread guide 8a will be switched at first into active yarn feeding position. The extension piece 2 will not be raised once during each cylinder rotation but instead will be normally disposed in clamping contact with dial cap 6 while the knitting of the main courses progresses, and correspondingly, the thread guide 8a will remain in active position throughout. When the main thread used for this purpose is to be Withdrawn from active knitting position at the termination of the knitting with this thread, then the thread guide 8a will be switched out of active position and extension piece 2 will be raised to permit the thread to pass therebeneath for clamping. Thereafter, the thread may be conveniently severed by separator 5, the thread end drawn into nozzle member 1 and clamping once more effected.

It will be appreciated, therefore, that in the initiating of the knitting of a thread in the ordinary case thread guide So will be moved into acitve yarn feeding position (FIGURE 6) and separator 5 will be energized although extension piece 2 will remain in clamping contact with dial cap 6, whereas in the terminating of the knitting of the thread, not only will thread guide 3a be moved 3,188, see

back to inactive position (FIGURES) but also extension piece 2 will be raised for thread clamping prior to severing of the thread end by energized separator 5 at the terminal edge of the last'aknitted course.

The artisan, of course, will be aware that when several knitting systems are carried out simultaneously, using multiple knitting stations, a thread clamping device in accordance with the inventionyaccompanied by a suitable thread separator element and thread guide may also be used at each station as desired. 1

It should be noted that whilethe particular thread clamping device is assigned to a thread guide 'or yarn feed'means 8 for the reinforcement thread F to be knitted into the tubular hose or other knitted goods along a particular portion thereof during each knitting course,

the normal knittingof the hose'will be simultaneously carried out at a knitting station other than that for" knitting the aforesaid reinforcement portion. Suitable con vention-al needle activating cam means may be employed for the separate knitting of the main thread'and the separate knitting of the reinforcement'thread' F, said ventiona-l separatorelement to clamp and cut the main thread being knitted when" the 1 knitting operation" with such threadis to be terminatedgas more'fullyappears from the copending application filed simultaneously herewith, Serial No. 93,8 04,filed March 6,1961, entitled:

Thread Changing Apparatus;

Whatis claimed is; i 1. In a straight bar knitting machine having knitting elements, yarn feeding means movable from an active yarn feeding position wherein yarn is fed to said knitting elements for knitting thereby to an in-active yarn feeding positionwh erein the yarn is-in non-knitting yarn feeding position wherein "yarnisi fed to said knitting elements for knitting thereby toan inactive yarn feeding position wherein. the yarn is in non-knitting position, and means for clamping and cutting said yarn when said yarn feeding means is'in active yarn feeding positioniand for releasing said yarnwhen said yarn feeding means is moved to active yarn feeding position, the improvement which comprises a'combinedyarn clamping and suction deviceincluding suction nozzle means andyarn engaging surface means arrangedforrelative movement "from a position out of 'yarnfclamping to a position intoyarn clamping contact with one-another when yarn feeding means is moved to inactive yarn feeding position, said yarn feeding means being positionedito move from active to inactiveyarn feeding position 'along a path between t said nozzle means and surface meanswhen saidnozzle means andsurface means are in open positionout of yarn clamping contact, whereby said' feeding means passes 'main' thread of the hose, being operablewith the con- 1 position, and means for'clamping and cutting said-yarn when said yarn feedingtmeans is inactiveyarn feeding position and for releasing said yarn when said yarn feeding'means is moved'toactive yarn feeding position,

the improvement which comprises a combined yarn clamping and suction device including suction nozzle I means and yarn engaging surface means arranged for:

relative movement from a position out' of yarn clamping contact to a position into yarn clamping contact with one another when said yarnfeeding means is moved to inactive yarn feeding position, *said surface means being provided with yarn engaging projection means insertable 9 into said suctionnozzle means during the yarn clamping contact, said projection means being adapted to engage the yarn to be clamped and carry a portion. thereof into 7 across the nozzle opening of said nozzle means to permit the yarn to extend; across such nozzle opening and be clamped thereat when said nozzle means andf surface means are moved to closed position in clamping contact with one anothensaid yarn engaging surface means being a cover surface adapted to seal off said suction nozzle means when in yarn clamping contact therewith.

3. Improvement according' to claim 2 'wherein said cover surface is provided withan elastic portion disposed thereon for sea-lingly engaging saidsuction nozzlejmeans while clamping Iyarn therebetween.

References Cited by the Examiner UNITED STATES PATENTS 1,727,784 a 9/29 Pulster 66-145 2,318,743 7 5/43 Brown 139-256 2,560,484. 7/51 Schoenster et'al. 66-145 2,567,540 9/51 Bergstrom et a1; z 139-256 2,743,877 5/56 Fiirst' 139-256.1.X 2,769,599 11/56 Fiirst 242-356 2,810,280 10/57 Rossman 66-145 X 2,824,436 2/58 Stack etal. 66-140 2,844,016. 7/58v 'Cobert".; 66-145 X 2,863,310 12/58 Miller 66-145 2,908,154; 10/59 ,ButlerI. 66-140 2,924,958: 2/60 Moyer, 66-140 2,956,593: a 10/60" Bauman'n" .Q 139-257 2,989,935 6/61' Butler 66-145 X 3,019,628 2/62 Page .66- 3,059,867,.10/62' Fiirst 242-356 3,067,778 12/62 fMerki 139-257 3,079,779 3/63 Butler et al. 66-14-5 3,120,747 2/64 Reading"; 66-1454 FOREIGN PATENTS I 1 810,225 *3/59 GreatBritain.

PARKER, Primary Examiner.

RUSSELL c. MADER, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,188,835 June 15, 1965 Werner Mayer et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 9, line 40, for "indicates" read indicate column 11, line 26, for "opreation" read operation column 12, line 5, for "active" read inactive line 12, before "yarn" insert said I Signed and sealed this 21st day of December 1965.

(SEAL) Attest:

ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents

Claims (1)

1. IN A STRAIGHT BAR KNITTING MACHINE HAVING KNITTING ELEMENTS, YARN FEEDING MEANS MOVABLE FROM AN ACTIVE YARN FEEDING POSITION WHEREIN YARN IS FED TO SAID KNITTING ELEMENTS FOR KNITTING THEREBY TO AN INACTIVE YARN FEEDING POSITION WHEREIN THE HARN IS IN NON-KNITTING POSITION, AND MEANS FOR CLAMPING AND CUTTING SAID YARN WHEN SAID YARN FEEDING MEANS IS INACTIVE YARN FEEDING POSITION AND FOR RELEASING SAID YARN WHEN SAID YARN FEEDING MEANS IS MOVED TO ACTIVE YARN FEEDING POSITION, THE IMPROVEMENT WHICH COMPRISES A COMBINED YARN CLAMPING AND SUCTION DEVICE INCLUDING SUCTION NOZZLE MEANS AND YARN ENGAGING SURFACE MEANS ARRANGED FOR RELATIVE MOVEMENT FROM A POSITION OUT OF YARN CLAMPING CONTACT TO A POSITION INTO YARN CLAMPING CONTACT WITH ONE ANOTHER WHEN SAID YARN FEEDING MEANS IS MOVED TO INACTIVE YARN FEEDING POSITION, SAID SURFACE MEANS BEING PROVIDED WITH YARN ENGAGING PROJECTION MEANS INSERTABLE INTO SAID SUCTION NOZZLE MEANS DURING THE YARN CLAMPING CONTACT, SAID PROJECTION MEANS BEING ADAPTED TO ENGAGE THE YARN TO BE CLAMPED AND CARRY A PORTION THEREOF INTO SAID SUCTION NOZZLE MEANS THEREWITH UPON YARN CLAMPING CONTACT WHEREBY TO FORM A LOOP PORTION IN THE YARN.

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