US3636730A

US3636730A - Textile mesh and method and apparatus for its manufacture

Info

Publication number: US3636730A
Application number: US865620A
Authority: US
Inventors: Josef Fecker
Original assignee: Texpatent GmbH
Current assignee: Texpatent GmbH
Priority date: 1968-11-26
Filing date: 1969-10-13
Publication date: 1972-01-25
Anticipated expiration: 1989-01-25
Also published as: JPS4812106B1; DE1811053A1; GB1259658A; CH496124A; CS151534B2

Abstract

This invention relates to a method and a circular knitting machine for manufacturing textile mesh products, particularly in the form of stockings and stocking tights, wherein a loop is transferred from one wale into an adjacent wale to prevent the formation of ladders. The transferred loop is moved laterally past an adjacent needle, whereupon the head of the needle is then lowered to engage one of the flanks of the transferred loop to move same downwardly. The transferred loop is then further moved laterally relative to the adjacent needle to cause the other flank of the transferred loop to pass over the head of the needle, thereby causing the plane of the loop to be rotated approximately 180*. The transfer element is then disengaged from the transferred loop, whereby the twisted transferred loop remains engaged with the adjacent needles.

Description

United States Patent Fecker 1451 Jan. 25, 1972 3,137,150 6/1964 Mishcon ..66/l98X FOREIGN PATENTS OR APPLICATIONS lnvenwfl Josef Fecker, Freudensladt, Wumeberg, 131,382 6/1902 Germany ..66/97 rm n r 148,722 3/1904 Germany ....66/97 73 Assisnee: Texpatem Gmb", Fribourg, Switzerland 762,875 1/1934 France ..66/l98 Filed; 13, 1969 Primary ExaminerWm. Carter Reynolds [2]] App] No 865 620 Attorney-Woodhams, Blanchard and Flynn [57] ABSTRACT [30] Foreign Applmmon Pnomy Dam This invention relates to a method and a circular knitting Nov. 26, 1968 Germany ..P 18 11 053.7 machine for manufacturing textile mesh products, particularly in the form of stockings and stocking tights, wherein a loop is [52] U.S. Cl ..66/95, 66/178, 66/198 transferred from one wale into an adjacent wale to prevent the [51] Int. Cl. ..D04b 15/02 formation of ladders. The transferred loop is moved laterally [58] Field of Search ..66/95, '97, l, 199, 198, 178 past an adjacent needle, whereupon the head of the needle is then lowered to engage one of the flanks of the transferred [56] References Cited loop to move same downwardly. The transferred loop is then further moved laterally relative to the adjacent needle to UNITED STATES PATENTS cause the other flank of the transferred loop to pass over the 2 780 082 2/1957 Zeruneith ..66/95 head needle, thereby causing the Planeofthe 'P be 3,470,715 10/1969 Panhum 66/95 rotated approximately 180. The transfer element is then disl 1/1970 pecker U 66/97 engaged from the transferred loop, whereby the twisted trans- 3'503'420 4/1970 Panhum et aL "66/95 ferred loop remains engaged with the adjacent needles.

901,264 10/1908 Scott 66/l99 X 2,195,218 3 1940 g i ......66/198 7 Dru-3mg figures Elk Q 33 g g? ao fj/ls 27

J

1, 11. 16 13 31:1 l \T l8 a I E; w 9 F4 3 PATENTED JAN25|972 3336730

sum

2 or 3 Fi g. 7

' INVENTOR.

diff F [ff/f6? TEXTILE MESH AND METHOD AND APPARATUS FOR ITS MANUFACTURE The invention relates to textile mesh products, particularly in the form of stockings and stocking tights, wherein several loops are transferred from their wale into an adjacent wale to prevent the formation of ladders, as well as to a method and a circular knitting machine for manufacturing these mesh articles.

As is generally known, ladders are produced in mesh when a loop breaks and releases the loop following in its wale so that the latter in turn slips through the loop holding it, releases this loop and so on until the wale has been completely removed. To prevent the formation of ladders, it is already known practice, e.g., from German Pat. specification No. 1,174,448 to extract loops from the wales during the manufacture of stockings and to transfer them from the side on to a needle which is adjacent to the needle producing the pertinent wale. In this connection, as disclosed in the said German specification, already czmt off loops can be gripped and transferred from the side onto an adjacent needle in the following course, however, as can be seen for example in British Pat. specification No. 446,670, loops still suspended on the needles can also be laterally expanded and also transferred in the same course onto an adjacent needle. In any case loops are produced with great frequency in the wales and are not or not only held in the preceding loop of said wale, but in the loop of an adjacent wale. A ladder can therefore only reach as far as a laterally transferred loop in the wale, since the transferred loop is not likewise released when the preceding loop is released.

Due to the necessary expansion of the transferred loops, a loop configuration relatively strongly penetrated in places and a mesh surface are produced, the smoothness of which leaves much to be desired. The problem underlying the invention is therefore to improve the appearance and surface quality of textile mesh articles of the type as described at the beginning. This problem is solved in accordance with the invention in that, in the case of the transferred loops, the thread forming the loop intersects between the top and the bottom of the loop.

The crossing of the thread forming the loop of the transferred loops produces a more closed loop configuration and a smoother surface of the textile mesh product. This is due to the fact that the crossing point lies in the vicinity of the expansion of the transferred loops so that the opening otherwise formed by the expansion is partially covered by the intersecting thread.

The known ladder-proof mesh is produced if, on a circular knitting machine having needles which are displaceable in longitudinal grooves of a needle cylinder having a circle of needles, transfer sinkers engage in the cast-ofi loops or in loops still suspended on the needles to expand and transfer the loops onto an adjacent needle. Another problem underlying the invention is to provide this method so that transferred loops are formed by thread interlacing between the top and bottom of the looped portion of the loop. This is achieved by the loops to be transferred being twisted through 180 during transfer relative to the plane of the looped portion and being held in the twisted position by the adjacent needle.

This twisting can be effected in any desired manner, for example by the transfer sinkers gripping the loops to be transferred by a hook-shaped working end and then being rotated once about themselves. This naturally requires a complicated drive for moving the transfer sinkers.

It is therefore simpler if, according to another advantageous feature of the method according to the invention, the looped portion of the loops to be transferred is laid by the transfer sinkers with the outer side of one flank of the loop against the stem of the adjacent needle below the needle head, then the other flank of the loop is drawn over the needle head while on thread intersection is formed inside and another thread intersection outside the circle of needles above the needle head, and finally the loop is released from the transfer sinkers while only the thread intersection lying inside the circle of needles is retained. This method does not require any twisting of the transfer sinkers about their longitudinal axis. It can be carried out on known circular knitting machines with transfer sinkers, such as disclosed in U.S. Pat. No. 3,470,715, 3,491,559 and 3,508,420. All that is required to put the new method into practice on these machines is to control the axial movement of the needles and, if need be, of thetransfer sinkers slightly differently with regard to time.

In a circular knitting machine comprising a rotating needle cylinder, in which displaceable needles are mounted and individually controlled in longitudinal grooves, and transfer sinkers with hook-shaped working ends which can be moved by means of a displaced carrier along a path forming a slight angle to the path of the needles at a speed differing slightly from the peripheral speed of the needles, the mesh according to the invention may be produced with particular ease and without thread expansion, if the rear sides of the hook-shaped working ends on the transfer sinkers are provided with a recess with which they can be guided over the heads of the needles taking up the transferred loops. Since one'flank of the loop is first laid against the stem of the needle below the needle head during the manufacture of the mesh product according to the invention by the previously described method, and then the other flank of the loop must be moved over the needle head, the transfer sinker holding the loop must be moved past very closely in front of and above the heads of the needles which receive the loop. This movement is greatly facilitated by the described recess.

The invention is described below with the aid of a practical embodiment together withthe drawings.

FIG. 1 shows a laterally transferred loop of the mesh according to the invention.

FIGS. Za-c show a loop transfer in the mesh according to the invention at three different stages.

FIGS. 3ab show a modification of a loop transfer in the mesh according to the invention at two stages. 7

FIG. 4 shows a schematic representation and prospective view of the transfer operation.

FIGS. 5a-c show the transfer of a single loop at three different stages.

FIG. 6 shows a vertical section through a circular knitting machine suitable for manufacturing the mesh product according to the invention.

FIG. 7 shows a detailed view of a needle and a transfer sinker of the machine as shown in FIG. 6.

In FIG. 1 two adjacent wales St, and St, are indicated by dot-and-dash lines. A loop Mv is extracted from the wale St, and transferred from the side into the wale 81,. As can be seen in FIG. 1, the thread F which defines the looped portion Msch crosses at the point of intersection K, between the foot Mf and the top Mk of the loop. This intersection is produced by rotating the loop Mv once through relative to the plane of the loop during transfer so that the flanks Mfl defining the loop Msch overlap one another at one point.

FIGS. 2a-c show the transfer operation in slightly more detail, three wales St and three courses MR,, MR, and MR, being shown therein. The last formed course MR, is still suspended on needles 3. A transfer sinker 26 then engages in the already cast-off loop Mv of the wale St, and the course MR: as, can be seen in FIG. 2a. The loop My is radially and laterally expanded and, after being rotated through 180 relative to the plane of the loop in the manner shown in FIG. 2b, is

transferred onto that needle 3 adjacent to the needle which formed the loop Mv. After the course MR, is cast off, the loop Mv is suspended in the wale St, and in the course MR, as can be seen in FIG. 20. The intersection point K, of the thread forming the loop Mv lies between the wales St and St,

It can be seen in FIGS. 3a and 3b that it is equally possible to transfer a loop M'v laterally from its own course MR, into an adjacent wale. In case also a point of intersection K, is produced between adjacent wales by rotating the loop relative to the plane of its looped portion through 180.

In FIG. 4 the operation of loop transfer can be seen in a simplified perspective view. The needles 3 rotate with the unshown needle cylinder in the direction of the arrow P. The course MR, is still suspended on the needles. From above the hook-shaped working ends 27 of transfer sinkers 26 engage in the loops Mv to be transferred. As can be seen in FIG. 4, the transfer sinkers 26 are guided along a path which forms a slight acute angle to the path of the needles 3. Moreover, the transfer sinkers move along their path at a speed which difl'ers slightly from the peripheral speed of the needles 3. The loops Mv to be transferred are thereby radially and laterally expanded and looped over the adjacent needle. As can be seen in the case of needle 3' in FIG. 4, the needles which take up the loops Mv to be transferred are guided upwards at such an early stage that the loops to be transferred bear against the stem 3b of the needle below the needle head 3a. By corresponding relative guiding of the needle and transfer sinker, as will be described in more detail below, the loop Mv is rotated through 180 relative to the plane of the loop so that it then has a thread intersection K, within the circle of needles, as can be seen in the case of the needle 3".

The operation of twisting the loops to be transferred can be seen in greater detail in FIGS. Sa-c. The outer side of flank Mfl, of the loop Mv is laid by the transfer sinker 26 against the steam 3b of the upward guided needle 3 below the needle head 3a. This stage is shown in FIG. 50. Then the needle 3 and the transfer sinker 26 are moved relative to one another so that the needle head 34 is lower in relation to the working end 27 of the transfer sinker 26. This can be achieved either by lowering the needle 3 or raising the transfer sinker 26 or by a combination of these steps. When the transfer sinker 26 continues to move past the needle 3 as a result of the different orbital speeds, the flank Mfl, of the loop Msch following in the direction of movement is moved over and beyond the needle head 3a in the manner shown in FIG. 5b, whereas the flank Mfl, below the needle head 3a bears against the needle stem 3b. The two flanks Mfl, and Mfl, intersect at two points, namely at K, within the circle and at K, outside the circle of needles. If the transfer sinker 26 is then moved upwards, it releases the loop Mv to be transferred. The latter slips back slightly and remains suspended on the needle 3 in the manner shown in FIG. 50. The intersection K, lying outside the needle is removed whereas the intersection K, lying inside the circle of needles is retained.

The desired thread'intersection in the transferred loop Mv is thereby achieved. The operation involves rotating the loop Mv to be transferred relative to the plane of the loop through 180.

A circular knitting machine by which the described operation can be performed can be seen in FIG. 6. This circular knitting machine comprises a needle cylinder 1, the outer periphery of which is provided with axially extending longitudinal grooves 2. Knitting needles 3 with needle heads 3a are guided for longitudinal displacement in the grooves 2. For example, conventional latch needles are used, partially in a long embodiment and partially in a short embodiment. The movement of the needles is effected by stationary cylinder cams 5 which are held in a cylinder cam wall 6 and act in known fashion upon laterally projecting feet of the needles 3. The needle cylinder 1 is provided with a main drive schematically represented at H and driven by a main drive shaft 7, a gear wheel 8 and a driving bush 10 having a gear rim 9, said bush being inserted in the needle cylinder 1 and rigidly connected thereto. The parts mentioned are supported on a machine frame 11 which also contains and/or carries the other unshown structural components of the machine which are of conventional design.

The upper edge of the needle cylinder 1 is surrounded by a sinker ring 12 which rotates synchronously with'the needle cylinder 1.

The sinker ring contains on its upper side grooves 13 extending radially to the needle cylinder, in which grooves castoff sinkers 14 are supported for longitudinal displacement.

The radial movement of the cast off sinkers 14 is effected by a stationary sinker carn ring 15 which is carried by a bearing support 16 rigidly connected to the machine frame 11. A thread feeding system is also mounted on'the bearing support, a thread guide being designated by numeral 17. Inside the needle cylinder 1 is mounted a funnel 18 through which the finished mesh article is drawn downwards.

The illustrated sinkers 14 are special sinkers which, apart from the principal problem of cooperating with the needles 3 to form loops during the manufacture of stockings, have the additional problem of temporarily retarding the first courses to produce the double welt. Sinkers of this type are described in German Pat. specification No. 1,169,072 and in US. Pat. No. 3,254,509.

In order that loops may be transferred in the above-mentioned manner in the mesh produced by the machine according to FIG. 6, there is provided a transfer mechanism generally designated by reference numeral 23. The essential component of this mechanism is a carrier body 24 which has a circular cylindrical shape in the illustrated embodiment, and its outer periphery is provided with axial guide grooves 25. The said transfer sinkers 26 together with their downward pointing, hook-shaped working ends 27 are guided for longitudinal displacement in these grooves. The carrier body 24 is rotatably held by a pivot 28 in bearing 29 which is in turn supported on a second bearing 30 rigidly mounted on the machine frame 30. The arrangement is such that the theoretical axis of rotation D, of the carrier body 24 is eccentrically staggered sideways in relation to the theoretical axis of rotation A of the needle cylinder 1. The eccentrically staggered arrangement lies in the direction of the peripheral zone of the needle orbit penetrated by the heads 3a of the needles 3, in which loop transfer is to take place. The diameter of the carrier body is selected so that the orbit described by the transfer sinkers 26 from the guide grooves 25 extends, in plan view, in the vicinity of the path of the needle heads 3a, when the needles 3 and the transfer sinkers 26 are moved through the loop transfer zone. The carrier body 24 is driven by the main shaft 7 via a pair of gears 31 at such a rotational speed that the peripheral speed of the carrier body 24 in the vicinity of the guide grooves 25 difl'ers slightly from that of the needle cylinder 1 in the vicinity of its grooves 2. In the loop transfer zone, therefore, the transfer sinkers 26 have a slightly higher or lower orbital speed than the needle heads 3. This variable speed is efiected by a corresponding selection of transmission ratios to the main shaft 7 and the needle cylinder 1, on the one hand, and to the carrier body 24, on the other hand.

The transfer sinkers 26 are moved through the guide grooves 25 by means of a cam member 32 rigidly connected to the stationary bearing 29, said cam member containing a control cam 33 in which the transfer sinkers 26 engage with lateral feet 34.

The described machine is so dimensioned that, in plan view, the orbit of the guide grooves 25 containing the transfer sinkers 26 partially penetrates the orbit of the needle heads 30.

The needles 3 and the transfer sinkers 26 of the described machine are controlled by the cam members 5 and the control cam 33 so that they execute the necessary movements for transferring and twisting the loops to be transferred, as shown in FIGS. 4 and Sa-c.

Since the hook-shaped working ends 27 of the transfer sinkers 26 must be guided directly in front of and above the needle heads 3a during these movements, it is advantageous to design the transfer sinkers 26 as shown in FIG. 7. The rear sides of the working ends 27 are provided with a recess 35 into which the head 3a of each needle 3 projects when the transfer sinker is moved over the needle head.

The mesh article according to the invention can also be produced on other knitting machines. It is essential that the loops to be transferred are rotated through relative to the plane of the loop during the transfer operation or that an intersection of the thread forming the loop is ensured.

Although a particular preferred embodiment of the invention has been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method for manufacturing a mesh product on a circular knitting machine having a plurality of needles disposed in a ring and movably mounted on a needle cylinder, said knitting machine also having a plurality of transfer elements disposed for engagement with loops of the mesh product for transfer thereof, said method comprising the steps of:

engaging a loop of said mesh product as disposed in one wale and as formed on one of said needles with one of said transfer elements; moving said one transfer element laterally relative to said one needle to cause said engaged loop to be laterally widened in a direction toward an adjacent loop located in an adjacent wale and engaged with an adjacent needle;

moving said transfer element laterally past said adjacent needle so that both flank portions of the engaged loop are positioned on one side of the shaft of said adjacent needle with one flank portion being positioned below the head of said adjacent needle and between said shaft and the other flank portion; then moving the other flank portion of the engaged loop over the head of said adjacent needle so that the other flank portion is disposed on the opposite side of the needle shaft from said one flank portion, whereby the flank portions of the engaged loop intersect at a point disposed inside the needle ring; and then disengaging said one transfer element from said engaged loop for causing said engaged loop to be hooked on said adjacent needle with said point of intersection being maintained and positioned within the needle ring.

2. A method according to claim 1, wherein the movement of said other flank of said engaged loop over the head of said adjacent needle causes said other flank to intersect said one flank at a second point located outside of the needle ring, and wherein disengagement of said engaged loop from said transfer element causes said second point of intersection to disappear.

3. A method according to claim 2, wherein said adjacent needle is moved downwardly after said one flank portion of said engaged loop has been positioned adjacent the shaft of the needle for causing the head of said adjacent needle to engage said one flank portion, and said transfer element then being continuously moved laterally relative to said adjacent needle to cause said other flank portion to be pulled over the head of said adjacent needle so as to be disposed adjacent the opposite side of the shaft of the adjacent needle.

4. The method according to claim 1, wherein said transfer element is moved on an arcuate path having a radius of curvature different from the radius of curvature of the path of movement of the needles, and said transfer element also being moved at a linear rate which is different from the linear rate of movement of said needles to permit the engaged loop to be transferred from said one wale of said mesh into engagement with said adjacent wale.

5. A method according to claim 1, wherein said engaged loop is initially disposed in engagement with said one needle, and said transfer element engaging said engaged loop and widening same laterally to permit same to be engaged with said adjacent needle.

6. A method according to claim 1, wherein said engaged loop is prior to engagement thereof by said transfer element already cast-off from said one needle, and said transfer element engaging said cast-off and widening same laterally whereby said loop is engaged with said adjacent needle and is thus transferred into an adjacent row and an adjacent wale.

7. A circular knitting machine for performing thereon the method according to claim 1 wherein said needles have hooklrke ends WhlCh are movable on a substantially circular path, and said transfer element having a hooklike end also movable on a substantially circular path disposed so as to form a small angle with respect to the path of movement of the needle heads, and drive means for causing the transfer element to move at a speed slightly different from the speed of rotation of the needles, the transfer element having a recess on the hooklike end thereof for permitting the transfer elements to be guided above and beyond the heads of' the needles during relative lateral movement therebetween.

i k l i

Claims

1. A method for manufacturing a mesh product on a circular knitting machine having a plurality of needles disposed in a ring and movably mounted on a needle cylinder, said knitting machine also having a plurality of transfer elements disposed for engagement with loops of the mesh product for transfer thereof, said method comprising the steps of: engaging a loop of said mesh product as disposed in one wale and as formed on one of said needles with one of said transfer elements; moving said one transfer element laterally relative to said one needle to cause said engaged loop to be laterally widened in a direction toward an adjacent loop located in an adjacent wale and engaged with an adjacent needle; moving said transfer element laterally past said adjacent needle so that both flank portions of the engaged loop are positioned on one side of the shaft of said adjacent needle with one flank portion being positioned below the head of said adjacent needle and between said shaft and the other flank portion; then moving the other flank portion of the engaged loop over the head of said adjacent needle so that the other flank portion is disposed on the opposite side of the needle shaft from said one flank portion, whereby the flank portions of the engaged loop intersect at a point disposed inside the needle ring; and then disengaging said one transfer element from said engaged loop for causing said engaged loop to be hooked on said adjacent needle with said point of intersection being maintained and positioned within the needle ring.

4. The method according to claim 1, wherein said transfer element is moved on an arcuate path having a radius of curvature different from the radius of curvature of the path of movement of the needles, and said transfer element also being moved at a linear rate which is different from the linear rate of movement of said needles to cause said transfer element to move laterally relative to said needles to permit the engaged loop to be transferred from said one wale of said mesh into engagement with said adjacent wale.

7. A circular knitting machine for performing thereon the method according to claim 1, wherein said needles have hooklike ends which are movable on a substantially circular path, and said transfer element having a hooklike end also movable on a substantially circular path disposed so as to form a small angle with respect to the path of movement of the needle heads, and drive means for causing the transfer element to move at a speed slightly different from the speed of rotation of the needles, the transfer element having a recess on the hooklike end thereof for permitting the transfer elements to be guided above and beyond the heads of the needles during relative lateral movement therebetween.