Needle cylinder and circular knitting machine

Abstract

A needle cylinder of a circular knitting machine includes a cylinder jacket having axial needle channels, knitting needles movable therein and an upper cylinder end for stitch formation having a radial groove between pairs of adjacent needle channels each having an insert forming a stitch formation surface with its insert surface protruding from the groove. Exchangeable, stitch formation surfaces form quickly replaceable inserts. Each insert is a spring lug including a lug foot overlapping the upper cylinder end at the side of the cylinder jacket or the side edge of an outer ring channel in the upper cylinder end and a lug terminal with a terminal part springily engaging behind a counter support projecting at the upper cylinder end at the cylinder's inner side or a side edge of an inner ring channel in the upper cylinder end. A circular knitting machine with the needle cylinder is also provided.

Claims

1. A needle cylinder of a circular knitting machine, the needle cylinder comprising: an upper cylinder end for stitch formation, an inner cylinder side having a counter support, a cylinder axis, a cylinder jacket having pairs of adjacent needle channels extending in alignment with said cylinder axis, and a cylinder jacket side; movable knitting needles disposed in said needle channels; said upper cylinder end having radially aligned grooves each disposed between a respective pair of adjacent needle channels; at least one insert disposed in each of said radially aligned grooves, said at least one insert having an insert surface protruding from a respective radially aligned groove and forming a stitch formation surface; said at least one insert each being a spring lug including a lug foot overlapping said upper cylinder end at said cylinder jacket side or overlapping a side edge of an outer ring channel provided in said upper cylinder end; said at least one insert each including an S-shaped lug terminal overlapping said upper cylinder end at said inner cylinder side or overlapping a side edge of an inner ring channel in said upper cylinder end; and said S-shaped lug terminal each having at least one terminal part resiliently engaging behind said counter support.

2. The needle cylinder according to claim 1, wherein said counter support is provided by a nose-shaped projection at an end of said inner cylinder side adjoining said upper cylinder end or of said inner ring channel, and said counter support at said inner cylinder side or in said inner ring channel is followed by an indentation for receiving said terminal part of said lug terminal resiliently engaging behind said counter support.

3. The needle cylinder according to claim 1, wherein each insert includes a support area lying planar on a groove base of said groove between said lug foot and said lug terminal, and each insert has respective free cuts provided between said support area and said lug foot and between said support area and said lug terminal.

4. The needle cylinder according to claim 1, wherein said cylinder jacket has an end adjoining said upper cylinder end, and a nose-shaped, projecting guidance for said lug foot provided at said end of said cylinder jacket.

5. The needle cylinder according to claim 1, wherein said insert includes a resetting recess area at said cylinder jacket side between said insert surface forming said stitch formation surface and said lug foot, said recess area being opposite to an end of said stitch formation surface facing a rib dial of the circular knitting machine.

6. The needle cylinder according to claim 5, which further comprises air nozzles directed toward at least one of said recess area or said lug foot.

7. The needle cylinder according to claim 1, wherein said lug foot is a closed, round clip.

8. A circular knitting machine, comprising a needle cylinder according to claim 1.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) Preferred embodiments of the present invention, their structure, function and advantages are explained in more detail by the following figures, wherein

(2) FIG. 1 schematically shows a cross-sectional view of a detail of a circular knitting machine according to the invention with an insert, which overlaps an upper cylinder end at the cylinder jacket side and at the cylinder's inner side, and with a retracted knitting needle;

(3) FIG. 2 schematically shows a cross-sectional view of the detail of the circular knitting machine of FIG. 1 with an extended knitting needle;

(4) FIG. 3 schematically shows a perspective illustration of the insert used as stripper in the circular knitting machine of the FIGS. 1 and 2 at the upper cylinder end;

(5) FIG. 4 schematically shows a cut cross-section view of an upper part of the circular knitting machine of the FIGS. 1 and 2 with an illustration of the insert fixed under spring tension;

(6) FIG. 5 schematically shows again a cut cross-section view of the part of the circular knitting machine shown in FIG. 4 with different hatching of subcomponents of the circular knitting machine;

(7) FIG. 6 schematically shows an upper part of the circular knitting machine of the FIGS. 1 and 2, wherein there is a knitting needle with its latch in the area of the insert and air nozzles are directed on said area of the insert; and

(8) FIG. 7 schematically shows a cut cross-section view of a further embodiment of an upper part of a circular knitting machine according to the invention with an insert, which overlaps an upper cylinder end at a cylinder's inner side and a side edge of an outer ring channel provided in the upper cylinder end.

DESCRIPTION OF THE INVENTION

(9) In the figures, same references indicate same or similar elements, which is why a description of an element, which is done in the following with regard to one figure, applies also for the same reference in other figures.

(10) The FIGS. 1 and 2 schematically show a detail in cut cross-section view of a circular knitting machine 10 according to the invention. The circular knitting machine 10 is a single cylinder circular knitting machine. The diameter of the circular knitting machine 10 is optional.

(11) The circular knitting machine 10 comprises a needle cylinder 1 being aligned upright and a rib dial 2 being transversely aligned to the needle cylinder 1. The needle cylinder 1 comprises a cylinder jacket 3 with a plurality of needle channels 4 spaced-apart in circumferential direction of the needle cylinder 1 and extending in axial cylinder alignment A with movable knitting needles 5 therein, which are here provided as latch needles, but which can also be other stitch forming needles in other embodiments of the present invention. The number of the needle channels 4 as well as the number of the knitting needles 5 therein are dependent from the gauge of the circular knitting machine 10, 10.

(12) The knitting needles 5 each comprise a needle shank 51, whereby they can be moved upwards and downwards with a lock mechanically coupled at the needle shank 51 not being shown in the present figures. The knitting needles 5 are held in the needle channels 4 by annular springs 52 in the embodiment shown.

(13) In the illustration of FIG. 1, the knitting needle 5 is in a reset position, while the knitting needle 5 in the illustration of FIG. 2 is in an extended position.

(14) The needle cylinder 6 comprises an upper cylinder end 6, being formed as a flattened cylinder upper edge running around the cylinder circumference. By the upper cylinder end 6 is the one cylinder end understood according to the invention from which the heads 53 of the knitting needles 5 protrude during the stitch formation process. In the upper cylinder end 6, radial running grooves 7 are provided, which extend between a pair of needle channels 4, respectively. The grooves 7 basically have a flat, horizontal extending groove base and are straight incisions running through the entire cylinder thickness.

(15) In each of the grooves 7, an insert 8 can be provided, respectively. The insert 8, which is used in the circular knitting machine 10 shown in the FIGS. 1 and 2, is shown enlarged in a perspective view in FIG. 3.

(16) The insert 8 is provided in form of a cross-section flat spring lug. The thickness of the spring lug is slightly smaller than the thickness of the groove 7 so that the insert 8 can be inserted easily but still tightly into the groove 7. The thickness of the insert 8 can be larger in its lower part to be inserted into the groove 7 than in its upper part protruding from the groove 7 in order to ensure a stable guidance of the insert 8 in the groove 7, on the one hand, and to provide enough space for the yarn in the stitch formation process, on the other hand. The thickness of the insert 8, however, can be also constant in all its areas. The radial extension of the insert 8 is larger than the radial extension of the groove 7.

(17) The spring lug comprises a lug foot 82 overlapping the upper cylinder end 6 at the side of the cylinder jacket 3. The lug foot 82 is provided as a closed round clip in the embodiment shown. As can be seen even more clearly in the enlarged illustration of an upper part of the circular knitting machine 10 in FIG. 4, the lug foot 82 encompasses a nose-shaped projecting guidance 31a for the lug foot 82 at the end of the cylinder jacket 3 bordering the upper cylinder end 6.

(18) Furthermore, the insert 8 comprises a lug terminal 83 overlapping an upper cylinder end 6 at the cylinder's inner side 9. The lug terminal 83 is S-shaped in the embodiment shown. The lug terminal 83 initially comprises a convex terminal part 831 projecting from the upper cylinder end 6, and thereupon opens into a concave terminal part 832 protruding to the cylinder's inner side 9. The terminal part 832 forms a spring element, which, as can be seen in FIG. 4, resiliently engages behind the counter-support 91 provided at the cylinder's inner side 9. The counter-support 91 is followed by a projection 92, in which the terminal part 832, which resiliently engages behind the counter-support 91, of the lug terminal 83 is received. In this embodiment of the present invention, the lug terminal 83 is provided at an end of the insert 8 directed to the cylinder's inner side 9.

(19) In other, not-shown embodiments of the present invention, the lug terminal, however, can also be spaced from the end of the insert 8 directed to the cylinder's inner side 9. In this case, an inner annular channel with a, for instance, nose-shaped counter-support intersecting the grooves 7 is provided in the upper cylinder end 6. The lug terminal is inserted into the inner annular channel such that it engages behind a side edge of the inner annular channel provided further away from the cylinder's inner side 9 and thereby engaging behind the counter-support provided at said side edge.

(20) The insert 8 protrudes from the groove 7 and forms a stitch formation surface or stripper surface with its insert surface 81. In the shown embodiment, the insert surface 81 comprises a first insert surface area 811 tilted downwards in the direction of the cylinder's inner side 9 and a second insert surface area 812 extending horizontally.

(21) The insert can comprise wear-reducing coating or treatment, which is at least provided in the insert surface area 812.

(22) As can be well-derived from example in FIG. 3 in relation to FIG. 5, in which the needle cylinder 1 is hatched for better clarity, comprises the insert 8 a support area 84, with which it lays plane on a groove base of the groove 7. Thereby, free cuts 85, 86 in the insert 8 are provided between the support area 84 and the lug foot 82 and between the support area 84 and the lug terminal 83.

(23) The insert 8 comprises at the side of the cylinder jacket 3, between the insert surface 81 forming the stitch formation surface and the lug foot 82, a recess area 88 reset opposite to the end 87 of the stitch formation surface facing the rib dial 2 of the circular knitting machine 10.

(24) FIG. 6 schematically shows an upper part of the circular knitting machine of the FIGS. 1 and 2, wherein a knitting needle 5 with its latch 54 is provided in the area of the insert 8 and air nozzles 11 are directed on said area of the insert.

(25) FIG. 7 schematically shows a cut cross-section of an upper part of another possible embodiment of a circular knitting machine 10 according to the invention.

(26) The circular knitting machine 10 comprises a needle cylinder 1 with a modified upper cylinder end 6 compared to the upper cylinder end 6 from the embodiment of the FIGS. 1 to 6. In the upper cylinder end 6, an outer annular channel 30 running in circumferential direction of the needle cylinder 1 is provided. The outer annular channel 30 intersects the grooves 7.

(27) Furthermore, the circular knitting machine 10 comprises a modified insert 8 compared to the insert 8 of the embodiments of FIGS. 1 to 6. Though the insert 8 comprises, just as the insert 8, a lug terminal 83 overlapping the upper cylinder end 6 at the cylinder's inner side 9 with the above-mentioned features, but does not engage behind the upper cylinder end 6 at the side of the cylinder jacket 3. Instead, the insert 8 comprises a lug foot 82, which engages behind a side edge 31 of the outer annular channel 30 lying further away from the cylinder jacket 3.

(28) The inserts 8, 8 interact with corresponding reciprocating motion elements 21, which are received in horizontal guiding channels in the rib dial 2 of the respective circular knitting machine 10, 10. The rib dial 2 is coaxially arranged to the needle cylinder 1, 1, respectively, and is fixed to it by a foot 55.

(29) Each movable element 21 has a finger 22 pointing radially in the direction of the cylinder's inner side 9 and runs over the insert surface 81 at its horizontal movement. Thus, in the present invention the inserts 8, 8 forming the stitch formation surfaces take over the function, which is done by movable strippers respectively sinkers in the state of the art. The movable elements 21 hold the stitch near the stitch formation surface, which is provided by the insert surface 81 of the inserts 8, 8, when the knitting needle 5 is lifted so that the stitch is not lifted up by the upward movement of the knitting needle 5, but is pushed in the direction of the needle cylinder center, whereby the contact of the stitch with the knitting needle 5 is maintained.

(30) While a movable element 21 has moved radially to the inside over the needle cylinder 1, 1, a knitting needle 5 moves upwards with the yarn. Thereupon, the finger 22 of the movable element 21 holds the yarn, whereby it is prevented that it is lifted up by the upward movement of the knitting needle. The upward movement of the knitting needle 5 is continued until the stitch is released from the opened latch 54 of the knitting needle.

(31) This results in an increased mechanical stress of the insert surface 81 in comparison to the other areas of the needle cylinder 1, 1. Hence, if the inserts 8, 8 are worn off with time, they can be removed by simply disconnecting them from the upper cylinder end 6, 6 and can be exchanged for new inserts 8, 8 by simply inserting the new inserts 8, 8 into the grooves 7 and by simply locating the new inserts 8, 8 onto the upper cylinder end 6, 6.

(32) The above-mentioned embodiments can be combined alternately with each other regarding individual features. The insert 8, 8 can be provided by one or a plurality of interconnected parts and/or by one or a plurality of materials or material combination(s).