CZ55793A3 - Circular knitting machine - Google Patents

Abstract

A circular knitting machine of elastic needle type in which the selection between those needles (3) to be flexed and those needles to be left in their normal configuration and hence travel along different contours of the knitting cams (25,26) is made by rocking selectors (23) housed in the tricks (2) below each needle (3), to act selectively so as to flex the needles (3) into their tricks (2) before they rise to seize the yarn feeds. <IMAGE>

Description

Circular knitting machine

Technical field

FIELD OF THE INVENTION The present invention relates to a circular knitting machine with grooved needle grooves in which needles are selected to move either along a path determined by the outline of the lock, located at a distance from the needle cylinder, or on another path determined by another outline of another lock. In particular, the invention relates to the selection of needles in this circular knitting machine to form a patterned or reinforced knitted fabric and to a device for selecting those needles to grasp the yarn from different feed points to form the knitted fabric.

BACKGROUND OF THE INVENTION

Circular knitting machines generally consist of one or two needle cylinders 1, which, as shown in FIG. 1, are provided with grooves 2 provided in their outer cylindrical surface. These grooves form a guide for the needles 2 which, in their vertical movement, form eyelet loops in cooperation with sinkers The number of grooves is equal to the number of needles which slide there by reciprocating action of the lifting and lowering locks, not shown in FIG. Circular knitting machines for knitting knitwear, such as stockings and socks, typically have 200 to 400 grooves and needles. The needle cylinder rotates, and with it the needles rotate as they return to the yarn at fixed angular positions when at the highest point of their path, from feed points consisting of one or more yarn guides that are selectively presented to the needle hooks that grasp the yarn.

Usually, only a portion of the needles available at the same time and in the same manner are used in the manufacture of knitted goods, except when the plain unsampled parts of the knit are knit, where all the needles work between their maximum and minimum levels, all supplied with yarn for Each row of knits and all move in the same way.

When a circular knitting machine does not form a smooth knit to form other types of knit, some needles must form eyelets and must therefore be lifted to the maximum level at the feed point to grasp the yarn while other needles must be raised to a medium level for shortening the yarn without closing the previous stitch, to form the catch stitch, or must be lifted with some delay so that it does not grasp the yarn being fed at this feeding point and therefore does not form new loops with it. In other words, needles must be selected. This means that before each inlet, it must be determined which and how many needles must travel a certain path, and which and how many other needles must travel a different path, or which should not move.

As can be seen from FIG. 1, this choice of needles 2 is made according to the known embodiment. auxiliary sinkers 4, which slide in the same grooves 2 as the needles 3 placed above them, so that these needles 3 move up to a higher level for gripping the yarn. After seizing the yarn is carried out by actuation of the needles so as to perform reciprocating motion, 'and by their own cams and counter-cams which are fixed relative to the cylinder, and which is not ^one shown in "FIG. 1 but shown in other figures.

1 shows a flexible auxiliary sinker 4, the lower end of which can be radially avoided. When this auxiliary sinker 4 has moved its needle to its working position, it withdraws from its node and returns back downwards. If the needle, after having completed its yarn grip and loop loop task and is therefore at its minimum level, does not need to grab the next yarn from the next yarn, it remains at that level until its operating auxiliary sinker or other machine members cause it again its upward movement.

The shank of the auxiliary sinker 4 is provided with a protrusion in its central part, i.e., a shank. the upper knee 5, which engages with its own lowering lock 6, to move the auxiliary sinker 4 downwards when it has completed its needle-lifting task 2 ^{at the} bottom of the auxiliary sinker 6, a lower one is provided an elbow 2 which engages a locking ring 8 provided with a lifting contour 9 for lifting the auxiliary sinker 8 together with a needle 2 above it, which is thus selected for gripping the yarn, and a proximity contour 10 which engages with its inner face the vertical face of the lower butt 7 to urge the lower part of the flexible jacks £ to the interior of the trick 2. When the lower part of the jack in this position the butt 7 can not cooperate with the raising contour 9 of the ring 2 ^and the jack remains lowered £. The lowering locks 6 and the lifting and approach contours 2 and 10 are of course angularly offset and act on each auxiliary sinker 6 at different times.

In circular knitting machines, when flexible auxiliary sinkers or conventional rigid auxiliary sinkers are used, the choice is generally controlled by keeping those auxiliary sinkers that correspond to the needles to be lifted by the lifting knee in a position pulled outwards to engage with the lifting contours, while those auxiliary sinkers that correspond to needles not to be selected remain in position within the groove. When .se, .p.o_us.i_j.i. The "flexible-auxiliary-pla-fe-ny", "my-tend" to move its lower knees 7 outward to engage the lifting contour 2 ^and are lifted, while using conventional auxiliary sinkers their pressing into the groove and pulling it out by means of suitably positioned locks, fixed relative to the needle cylinder.

The auxiliary sinkers 4 are held in position so that bending or displacing their lower part does not cause their upper part to leave the groove, for example by using one or more circular springs 12 fixedly connected to the needle cylinder 1, which surround the upper part of the auxiliary sinkers. The annular springs are held in position by circumferential grooves in the needle cylinder, so that they abut internally to the surface of the needle cylinder. FIG. 1 further shows schematically a selector 11 which will allow the auxiliary sinker 4 to move outwards and lift it on the lifting contour 9 or keep it pushed in its groove so it stays down. Conventional selections employ mechanical selectors operating on a series of intermediate butts, but this type of selection represents a significant limitation both in operation and in the number of possible choices.

. Recently, circular knitting machines employ electromagnetic selection devices which allow for a higher selection speed and a greater number of programmable selections, which has the advantage of increasing production productivity and a greater number of possible patterns.

These selectors are divided. essentially into two categories, namely fixed devices which do not rotate with the needle cylinder and are located in front of each feed point to which the auxiliary sinkers arrive as they rotate, and on a selector device rotating with the needle cylinder ( and its auxiliary sinkers), which are therefore always located in the auxiliary sinkers and can act on them at any time and not only in the very short time in which the auxiliary sinkers pass through them. ' This second - type option is also made

before the auxiliary sinkers pass before the feed point, but in this case there is more freedom in terms of synchronization requirements and time constraints available for dialing, but requiring a greater number of dials equal to the number needles and not the number of feed points. Selector devices and methods for selecting both types working with both rigid and flexible auxiliary sinkers are described in published European patent applications. No. 0 379 234, 0 431 6.74, 0 441 005, 0 479 371 and in the Italian patent application no. 22172 A / 90 of the same applicant.

Those methods in which auxiliary sinkers are used in circular knitting machines for needle selection require the use of selections which are complicated and must be used. the needle cylinder 1 long enough to accommodate the needles 3, the auxiliary sinkers 4 and any vertical selector actuators as mentioned in said patent applications.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a circular knitting machine which does not use vertically moving auxiliary sinkers and which instead is selected directly on the needles.

SUMMARY OF THE INVENTION

This task is accomplished by a circular knitting machine with grooved needle rollers - in which the needles are selected to move either along a path determined by the outline of the lift lock located at a distance from the needle cylinder or on another path determined by another outline of another lift lock. located at a smaller distance from the needle cylinder according to the invention, the essence of which is that the needles. They are resilient with needles for which the selection operation is performed by causing them to bend into the grooves or not to bend, so that their knee protrudes to a smaller or greater distance from the respective. grooves, wherein

the bent needles can only rise to the contour of the second lock with their knees, while the unneeded needles can rise to the contour of the first lock, whose upward pressure begins before the upward pressure of the second lock, and that the needles are bent by swinging selectors arranged under the needles and swinging a lower protrusion, wherein each needle is connected to. a swinging sinker which pivots in the same groove as its attached needle and tilts or does not tilt into its groove when the needles reach their lowest level by the lowering lock, and wherein: the swinging sinkers that are tilted into their groove are those that correspond to needles to be bent into their groove and which therefore cannot slide along the contour of the first lock but can slide along the contour of the second lock.

According to a preferred embodiment, the groove is formed with a recessed profile that allows the needle to bend into itself.

According to a further preferred embodiment, the swinging development sinkers are provided with one or two. a plurality of butts at a level corresponding to the radially pressurized actuators, wherein the tilting of the swinging platinum is achieved by applying the swinging actuator to one of its butts and returning out of the swinging platinum after interrupting the action of the swinging actuator is achieved by a spring acting against and located in the groove.

Finally, according to a further preferred embodiment, the circular knitting machine is provided with an axially movable second lock capable of assuming three levels corresponding to the stitch-free position, the stitch-holding position of the inactive position of the needles moving by its knee along the contour of the second lock. in accordance with the feed point of the circular knitting machine, the second lock having an outline such that the needles traveling thereafter are raised with a considerable delay compared to the lifting of the needles traveling after the first lock.

Summary of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 2 shows a vertical cross-section of the needle cylinder, with the needle in the left position and the right in the bent position; FIG. a cross-section of the needle cylinder and, in side view, the shape of the locks moving the needles. . . ·. ·. ··

DETAILED DESCRIPTION OF THE INVENTION

As can be seen from FIG. 2, the needle cylinder 1 is provided with grooves 2 having a recessed profile 2a which allows the needles 3 / which slide in their grooves 2 to evolve with their lower part into their groove 2 to allow their immersion to be immersed. the elbow 20 into the recessed profile 2a. The needle 2 is bent by means of a radial thrust lock 21. In Fig. 2, the necessary and bent needle 2 is shown on the left.

The needle 3 is provided with a knee 20 for engagement with its lift and lower lock. Underneath the knee 20 is a projection 22 which engages the projection 24 of the pivotable sinker 23. When the needle cylinder is rotated, all needles 2 are lowered by the lowering lock 29 and the counterlock 30 described below, in which position they are subject to selection. In this maximum lowering position, the projection 22 below the knee 20 of the needle 2 engages the projection 24 of the pivotable developing sinker -23. At its lower end, the pivoting selector 23 is provided with a recess 12 which abuts the edge provided with a projection 13 with a rounded profile adapted to the shape of the recess, thereby allowing the upper end of the pivoting selector 22 to swivel. of the sinker 22 'around said hinge is limited by an outer ring and a spring 15 disposed in the groove 2 and urging the pivotable developing sinker 23 toward the outer ring 14.

On the outside of the central portion of the pivotable sinker 23 are provided nodes 16, which are used in the same way as the nodes of the sinker of the known embodiment. These nodes 16 are provided in a sufficient quantity to provide the desired number of selection combinations. All surplus nodes 16 are removed from the pivoted platinum 23 except for those required to make contact with one or more radial thrust actuators 18 at their level.

Many types of radial pressure actuators are known for the selection of the butts 16, see for example Italian Patent Application No. 23287 A / 85, European Patent Application 0 397 254 and European Patent 0 190.803 of the same applicant.

These controls therefore work. to those swinging platinum 23 whose undeleted. the knee 16 lies at their level, while the other swinging selectors 22 (which have their remaining knees 16 at other levels) are not selected. When the pivotable sinker 23 is pushed into the groove 2 and causes the needle 3 above it to deflect, it is. spring 15 elastically ·· Ρ ''' _f · loaded. When the pressure of the pressure actuator 18 ceases, it releases. the spring 15 to press the swinging sinker 23 against the outer ring 14. If the swinging sinker 23 is pushed in, see right part of FIG. 2, the projection 24 engages both the vertical portion and the vertical portion of the projection 22 of the butt 20 and does not allow the butt 20 rise to the contour of the first lock 25 located at the outermost position relative to the needle cylinder 1, but only allow it to climb along the contour of the second lock 26 which is located closer to the needle cylinder 1 and which has a different shape as described below.

and

If the swinging selector 23 is not pushed inside the groove 2 (see left part of FIG. 2), the projection 24 does not cause a deflection of the knee 20, which therefore follows the contour of the first lock 25.

The needles 2 are held in position by one or more springs 27 that surround their upper portion. These spring 27. are placed in circumferential grooves 28 in the cylinder 2 · spring 27 must exert sufficient force against the force causing the needle to avoid 3 to swinging selectors 23 .. platinum avoid causing only the lower part of the needle 2 ^and not pivoting of the upper part of the groove 2.

Fig. 3 shows a vertical cross-section of the needle cylinder 1 and the side view of the locks that move the needles 3, with the swinging sinker 23 being shown with only one left knee 16 which is pushed inward by its thrust actuator 12. left. The locks remain stationary and the needle cylinder 1 rotates with its needles 2, whose nodes 20 then engage the contours of the locks as they arrive.

The knee 20, shown at the far right, engages the lowering descending contour of the lowering lock 29 until it reaches. When the needle 3 is at this lowest point, the swinging selector 23 is either pushed or not pushed in to make a selection. The selection area is indicated by the segment S. The selection must be made before the needles meet the assembly consisting of the locks 25 and 26. If the needle 2 has not been pushed into the groove 2 by its pivotable selector 23, it will return outward and have its knee. 20 is a steep contour of the first lock 25, which is quite steep and reaches the initial portion of the feed area indicated by the segment A in which the yarn guides are provided which present the yarn to the feed hook 3.

Upon their lifting movement after the first lock 25, the needles 3 are freed from the loop loops formed during the previous knitting cycle; that move along the shank of the needle 2 / so that only the yarn (or yarn) is grasped in the hook of the needle 2 during this lifting, the previous loop being released for the next lowering of the needle 2 ·

If the needle 3 is engaged by its knee 20 with the protrusion 24 of the pivotable developing sinker 23, its knee 20 projects less outwardly than in the previous case. The radial counter-force exerted by the bent needle 2 on the pivotable developing sinker 23 is directed against the pressure of the pressure actuator 18.

Thus, the knee 20 cannot be lifted on the rising contour of the first lock 25, and is raised only to the contour of the second lock 26, which is closer to the needle cylinder 1. The track followed by needles 2 rising at the second lock 26 and knitted fabric produced ,, this pathway are therefore different from the track and the knitting needles 2 moving along the first cam 25. the needle 3 is lifted and no longer subjected to the effect of the pressure projection 24 swinging selectors 23rd pressure controller 13 has completed its úkoi- ^:: a _' can. to go back to rest. position.

According to a preferred embodiment of the invention, the second lock 26 is provided with an adjusting element allowing the second lock 26 to assume different heights so that the needles moving therethrough can act differently, namely:

getting rid of the stitch and grasping a different lead than the needles 2 / which move along the first lock 25, by raising to the same level as the other needles 2 / but with a delay, holding the stitch, i.e. grasping the yarn without getting rid of it

-------- created by the eye, by raising to the middle level,

- they move down without forming a new loop because the new yarn is not grasped.

This movable second frame 26 is described in more detail in the co-pending Italian application MI 91 A 003239 of the same applicant.

One that is not raised or, more precisely, their knees 20 then touch the contour of the lowering lock

29, which all returns them down to form the loop loops with the yarn they have just picked up and to close the previously formed loop loops carried on their pitch.

PATENT CLAIMS -

Claims (4)

1. A circular knitting machine with a needle cylinder provided with grooves (2) in which the needles (3) slide which are selected to move either along a path defined by the contour of the lift lock (25) located at a certain distance from the needle cylinder. a different path defined by another contour of another lifting lock (26) located at a smaller distance from the needle cylinder, characterized in that the needles (3) are flexible needles for which the selection operation is performed by causing them to bend into the grooves (2) or so that their knee (20) protrudes to a lesser or greater distance from the respective groove (2), wherein the bent needles (3) can only climb to the contour of the second lock (26) by their elbows (20) while the non-bent needles (3) can rise to the contour of the first lock (25), whose upward pressure starts before the upward pressure of the second lock (26), and that the needles (3) are avoided by the pivoting actions a sinker (23) disposed beneath the needles (3) and swinging around the lower protrusion (13), each needle (3) being connected to a pivotable developing sinker (3) that pivots in the same groove (2) as its attached needle (3) and tilts or does not tilt into its groove (2) when the needles (3) reach their lowest level by the action of the lowering lock (29), and wherein the swinging development sinkers (23) are inclined into their groove (2) are those which correspond to the needles (3) to be bent into their groove (2) and which therefore cannot slide along the contour of the first lock (25) but can slide along the contour of the second lock (26). Circular knitting machine according to claim 1, characterized by. in that the groove (2) is formed with a recessed profile (2a) which allows the needle (3) to bend into itself. A circular knitting machine according to claim 1. 1, characterized in that the swinging platinum (23) is provided with one or more knees (16) at a level corresponding to the radially pressing actuators (18), wherein the tilting of the swinging platinum (23) is achieved by applying a pressure actuator (18) to one of its knees (16) and returning out of the pivotable selector (23) after the pressure actuator (18) has been interrupted is achieved by a spring (15) opposing and disposed in the groove (2). Circular knitting machine according to one or more of the preceding claims, characterized in that it is provided with an axially displaceable second lock (26) capable of asserting three levels corresponding to the deprivation position of the stitch, the position of holding the stitch to the inactive position of needles (3) its knee (20) along the contour of the second lock (26), which is positioned in accordance with the feed point of the circular knitting machine, the second lock (26) having an outline such that the needles (3) traveling thereafter are raised with considerable delay as opposed to lifting needles (3) traveling along the first lock (25). List of reference numbers needle cylinder 1 groove 2 recessed profile 2a needle 3 flexible auxiliary sinker 4 upper knee 5 lowering lock 6 lower knee 7 lock ring 8 2stroke contour 9 approach contour 10 selector 11 recess 13 outer ring 14 spring 15 knee 16 pressure actuator 18 elbow 20 projection 22 pivotable sinker 23 projection 24 first lock 25 second lock 26 spring 27 circumferential groove 28 lowering lock 29 counter-lock 30 segment S segment A