EP3770312B1

EP3770312B1 - Weft knitting machine capable of changing yarn positions

Info

Publication number: EP3770312B1
Application number: EP19187868.5A
Authority: EP
Inventors: Hsin-Chung Lee
Original assignee: Pai Lung Machinery Mill Co Ltd
Current assignee: Pai Lung Machinery Mill Co Ltd
Priority date: 2019-07-23
Filing date: 2019-07-23
Publication date: 2022-09-14
Anticipated expiration: 2039-07-23
Also published as: EP3770312A1; ES2930115T3; PT3770312T

Description

FIELD OF THE INVENTION

The invention relates to a weft knitting machine knitting structure, in particular to a weft knitting machine knitting structure with changeable yarn positions.

BACKGROUND OF THE INVENTION

Plating, also known as yarn overlapping, refers to the simultaneous feeding of two differently colored yarns during knitting, causing a technical face and a technical back of a knitted fabric to appear differently colored. However, in order to increase the color or pattern change of the fabric, it has been proposed in the prior art to change the position of the two yarns fed during the knitting process so as to change the color of the plated on the technical face, and the fabric surface thereof is shown in Fig. 1. As such, the foregoing knitting techniques are known in the art as Jacquard.
US 9 834 871 B2 discloses a device and a method for knitting interchanged plating on a technical face for a flat bed knitting machine which includes at least one needle bed that has a plurality of latch needles, a plurality of sinkers and a carriage comprises the steps of: forming an indentation and a nose protrusion at each sinker; controlling the latch needle to move in a staged stitching displacement; feeding a first and a second coloration yarns to the flat bed knitting machine simultaneously; pushing the yarns via the nose protrusion of the sinker to knit a standard plating and continuing the knitting operation through the standard plating to form a technical face of the fabric; and controlling the latch needle to perform an interchanged stitching displacement, and ordering the sinker to pick up and release the yarns through the nose protrusion and the indentation to knit an interchanged plating.
US 2 273 811 A relates to a method and apparatus for making knitted fabrics having design effects thereon. In an independent needle knitting machine, there are provided reverse plating means comprising means for simultaneously feeding two yarns in plating relation, and needle actuating means in association with predetermined plating needles and predetermined reversing needles for bringing them into operative -engagement with said yarns, said actuating means including means operative upon said plating needles to cause them to take both of said yarns, means operative upon said reversing needles to cause them to take a selected one of said yarns, means to close the latch of each reversing needle after operatively taking its yarn, and means to hold each nonselected yarn in front of the closed latch of the coacting reversing needle, whereby said non-selected yarn in the following plating needles will be carried forwardly therein prior to the "loop drawing".
US 4 328 686 A discloses an improvement for knitting pattern areas with hosiery knitting machines having a rotatable cylinder carrying latch needles therein, a knitting station at which a plurality of yarn feed fingers are independently movable into and out of yarn feeding positions for feeding background yarn at a basic level and pattern yarn at a higher level above the cylinder, and means for selectively positioning the needles at either a basic position for receiving only background yarn or an extended position for receiving both background and pattern yarn, the improvement being an auxiliary feed finger for feeding background yarn at a level more closely spaced from the cylinder than the basic level to needles at the basic position and below the latches of needles at the extended position for floating of the background yarn in knitted pattern areas behind loops of pattern yarn formed by extended position neeldes. An independently rotatable pattern drum sleeve, operatively associated with the yarn feed fingers and auxiliary finger to selectively render them inoperable in response to control thereof by the machine pattern drum, is provided to further expand the machine capability for color effects.
In patents US 1,666,794 , US 1,950,405 , US 3,157,035 , US 2,616,276 , CN 104532458 A , WO 00/15890 A , etc., the positions of two yarns fed are changed by the structure of a yarn carrier itself or a collocation structure. However, since the yarn carrier is still at a distance from the position where the weft knitting machine performs knitting, even though the yarn carrier can immediately change the position of the yarn, a plurality of remotely located needles can still grab the yarns at the unchanged position, resulting in the problem of residual shadow on the fabric, as indicated at an after image 90 in Fig. 2.
In addition, there are also embodiments for accomplishing the need for yarn change through a variety of sinkers, such as disclosed in U.S. Patent No. 1,977,590 and CN Patent No. 2,249,253Y , but such an embodiment would result in a significant reduction in the number of needles that can be deployed per opening of the weft knitting machine and would not be suitable for the current industry's need for needle number.

SUMMARY OF THE INVENTION

The main purpose of the present invention is directed to solve the problem in the prior art that a yarn carrier used for knitting yarns would cause after images appeared on a fabric easily.
The secondary object of the present invention is directed to solve the practical problems deriving from the fact that yarn changes are required to be carried out in a variety of sinkers in conventional techniques.
In order to achieve the above object, the present invention provides a weft knitting machine capable of changing yarn positions, and capable of feeding a facing yarn and a bottom yarn during knitting. The weft knitting machine comprises a plurality of sinkers and a plurality of needles. The plurality of sinkers is respectively arranged adjacent to one of the plurality of needles. Each of the plurality of sinkers comprises a belly, a nose connected with the belly, and a throat between the belly and the nose. Each of the plurality of sinkers is guided to perform a linear displacement movement,so as to position the facing yarn above the nose and the bottom yarn in the throat during a process of the linear displacement movement. The weft knitting machine further comprises a plurality of needles respectively arranged adjacent to one of the plurality of sinkers, and a motion direction of plurality of needles perpendicular to a direction of the linear displacement movement. The plurality of needles respectively includes a hook and a latch for performing a closing action relative to the hook, wherein in a first needle retracting track, each of the plurality of needles controls the latch performing a closing action at a latch closing time point; and in a second needle retracting track, each of the plurality of needles controls the latch performing a closing action before the latch closing time point. Each of the needles in the first needle retracting track knits a standard plating without changing positions of the facing yarn and the bottom yarn in the hook; and each of the plurality of needles in the second needle retracting track comes out first and knits an interchanged plating with changing the positions of the facing yarn and the bottom yarn in the hook. In the second needle retracting track, the latch drives the bottom yarn to make the bottom yarn pushed by the nose of one of the plurality of sinkers when one of the plurality of sinkers adjacent to each of the plurality of needles does not restrict positions of the facing yarn and the bottom yarn.
In one embodiment, the weft knitting machine comprises a needle guide plate comprising the first needle retracting track and the second needle retracting track to guide the plurality of needles, and a sinker guide plate guiding the plurality of sinkers to perform the linear displacement movement. Further, the weft knitting machine comprises a needle selector for controlling each of the needles.
In one embodiment, each of the plurality of sinkers has only a single motion track, and the motion track cycles through a first retraction section, a first push-out section subsequent to the first retraction section, a second retraction section subsequent to the first push-out section, and a second push-out section subsequent to the second retraction section. The time point for the latch of each of the plurality of needles generating the closing action in the first needle retracting track is that one of the plurality of sinkers adjacent to the latch moves to the second retraction section, and the time point for the latch of each of the plurality of needles generating the closing action in the second needle retracting track is that one of the plurality of sinkers adjacent to the latch moves to the first push-out section.
In one embodiment, the top yarn and the bottom yarn are different in color.
Through the implementation of the invention and compared with the conventional application, the invention has the following characteristics: according to the weft knitting machine disclosed by the invention, the change of the yarn position is carried out in the hook comprising the facing yarn and the bottom yarn, so that the knitting requirement for changing yarns can be quickly performed, and the after image on the fabric is specifically avoided. Besides, the weft knitting machine provided by the invention can achieve the purpose of quick yarn changing and knitting without greatly modifying the integral structure.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic diagram of fabric surface when the yarn is changed correctly in the fabric.
Fig. 2 is a schematic diagram of the fabric with a residual shadow.
Fig. 3 is a structurally schematic view showing a weft knitting machine according to one embodiment of the present invention.
Fig. 4 is a comparison diagram of tracks of a needle and a sinker according to one embodiment of the invention.
Fig. 5 is a schematic diagram of the action of a sinker according to one embodiment of the present invention.
Fig. 6 is a needle retracting action schematic diagram when a needle moves in a first needle retracting track according to an embodiment of the invention.
Fig. 7 is a schematic diagram showing the position of the top yarn and the bottom yarn during standard plating according to one embodiment of the invention.
Fig. 8 is a needle retracting action schematic diagram (1) when a needle moves in a second needle retracting track according to one embodiment of the invention.
Fig. 9 is a needle retracting action schematic diagram (2) when a needle moves in a second needle retracting track according to one embodiment of the invention.
Fig. 10 is a schematic diagram showing the positions of a top yarn and a bottom yarn in a hook during interchanged plating according to one embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The detailed description and technical contents of the present invention will now be described with reference to the drawings as follows:

Referring to Figs. 3, 4 and 5, the present invention provides a weft knitting machine 10 with changeable yarn positions, which is provided on a needle bed 20 of a weft knitting machine, and the weft knitting machine is a circular knitting machine. The weft knitting machine 10 comprises a plurality of sinkers 11 and a plurality of needles 12, wherein the plurality of sinkers 11 are arranged at equal intervals, and each of the plurality of sinkers 11 comprises a belly 111, a nose 112 connected with the belly 111, and a throat 113 between the belly 111 and the nose 112. A yarn-bearing surface 114 of each of the plurality of sinkers 11 is located on a side of the nose 112 without facing the throat 113, and the yarn-bearing surface 114 is not limited by a plane and is able to be designed according to implementation requirements. On the other hand, a yarn-pushing surface 115 is located at an end of the nose 112, the yarn-pushing surface 115 is flat in this embodiment, but is not so limited and is able to be designed according to the implementation requirements. Further, each of the plurality of sinkers 11 of the present invention is guided by a sinker guide plate 13 to perform a linear displacement movement 116. Further, the linear displacement movement 116 is actually a one-dimensional movement.
Referring to Figs. 3, 4, 5 and 6, the plurality of needles 12 are disposed adjacent to one of the plurality of sinkers 11 respectively, that is, each of the plurality of needles 12 is disposed between any two of the plurality of sinkers 11 that are adjacent. Each of the plurality of needles 12 comprises a hook 121 and a latch 122 performing a closing action where is relative to the hook 121. Further, when each of the plurality of needles 12 moves to hook a yarn, the latch 122 performs opening relative to the hook 121 so that the yarn is able to enter the hook 121. Furthermore, when each of the plurality of needles 12 is retracted, the latch 122 performs the closing action in the direction towards the hook 121 due to the action of a previous knitted plating 50, closing the originally open portion of the hook 121. Further, the plurality of needles 12 of the present invention are arranged in a direction that the open portion of the hook 121 faces the throat 113 adjacent to one of the plurality of sinkers 11, as shown in Fig. 6. Further, the motion direction of the plurality of needles 12 of the present invention is perpendicular to the direction of the linear displacement movement 116, and the plurality of needles 12 are controlled by a needle guide plate 14 respectively for guiding each of the plurality of needles 12 to move in a first needle retracting track 40 or a second needle retracting track 41. Further, each of the plurality of needles 12 is controlled by a needle selector (not shown in the drawings). Furthermore, a time point for the latch 122 of each of the plurality of the needles 12 performing the closing action in the second needle retracting track 41 is earlier than in the first needle retracting track 40.
Referring to Figs. 3, 4 and 5, the weft knitting machine 10 receives a facing yarn 30 and a bottom yarn 31 positioned below the facing yarn 30 that are fed by a yarn-feeding device (not shown in the drawings) during knitting. In one embodiment, the color of the facing yarn 30 is different color from the color of the bottom yarn 31. Specifically, herein presenting inaction of the plurality of needles 12 explains the relationship among each of the plurality of sinkers 11, the facing yarn 30 and the bottom yarn 31 for the moment. Thus, each of the plurality of sinkers 11 is guided by the sinker guide plate 13 to carry out the linear displacement movement 116, and in the process of the linear displacement movement 116, the facing yarn 30 is always positioned above the nose 112, and the bottom yarn 31 is always positioned in the throat 113. Further, each of the plurality of sinkers 11 only performs one-dimensional movement.

With reference to Figs. 4, 6 and 7, the operation of each of the plurality of needles 12 is explained by illustrating the overall operation of the weft knitting machine 10. Accordingly, when each of the plurality of needles 12 moves in the first needle retracting track 40, each of the plurality of needles 12 knits a standard plating without changing positions of the facing yarn 30 and the bottom yarn 31 in the hook 121, and the so-called "the standard plating" refers to a plating in which the facing yarn 30 is positioned above the bottom yarn 31 when viewing from a technical face of a fabric. Then referring to Figs. 8, 9 and 10, when each of the plurality of needles 12 of the present invention moves in the second needle retracting track 41 that one of the plurality of sinkers 11 adjacent to each of the plurality of needles 12 does not restrict positions of the facing yarn 30 and the bottom yarn 31, the latch 122 dials the bottom yarn 31 to make the bottom yarn 31 be pushed by the nose 112 of the plurality of sinkers 11, so as to change the positions of the facing yarn 30 and the bottom yarn 31 in the hook 121, then to knit an interchanged plating. The so-called "the interchanged plating" refers to a plating in which the facing yarn 30 is positioned under the bottom yarn 31 when viewing from the technical face of the fabric. Thus, the motion of the plurality of needles 12 in the first needle retracting track 40 or the second needle retracting track 41 determines whether the weft knitting machine 10 of the present invention changes the position of the yarn.
Referring to Fig. 4, 6 and 7, each of the plurality of sinkers 11 only comprises one motion track 42 that recurring operations of a first retraction section 421, a first push-out section 422 subsequent to the first retraction section 421, a second retraction section 423 subsequent to the first push-out section 422, and a second push-out section 424 subsequent to the second retraction section 423. Here, the retraction of is defined that each of the plurality of sinkers 11 moves in a direction opposing to the feeding point of the facing yarn 30 and the bottom yarn 31, so that the facing yarn 30 and the bottom yarn 31 are not restricted by the plurality of sinkers 11. Further, the push-out action is defined that after the retraction each of the plurality of sinkers 11 moves toward the feeding point of the facing yarn 30 and the bottom yarn 31, so that the facing yarn 30 and the bottom yarn 31 are restricted by the plurality of sinkers 11 and unable to change position. Thus, each of the plurality of sinkers 11 in each section of the motion track 42 varies the position continuously, rather than being located at a single location. Referring to Figs. 4, 6 and 7, when each of the plurality of needles 12 moves in the first needle retracting track 40, the time point for the latch 122 generating the closing action is that one of the plurality of sinkers 11 adjacent to the latch 122 moves to the second retraction section 423. Thus, the facing yarn 30 and the bottom yarn 31 are hooked by the hook 121 in a state of being initially fed into the weft knitting machine 10. Referring to Figs. 4, 8, 9 and 10, on the other hand, when each of the plurality of needles 12 moves in the second needle retracting track 41, the time point for the latch 122 generating the closing action is that one of the plurality of sinkers 11 adjacent to the latch 122 moves to the first push-out section 422. In detail, the time point for the latch 122 generating the closing action is not at the end point of the first push-out section 422, and is a stage that each of the plurality of sinkers 11 still does not restrict the position of the facing yarn 30 and the bottom yarn 31 in the first push-out section 422 instead. Therefore, when the latch 122 of each of the plurality of needles 12 performs the closing action, the bottom yarn 31 is dialed so that the bottom yarn 31 is diverged from the original position and is positioned on the displacement track of the nose 112 adjacent to one of the plurality of sinkers 11, and the plurality of sinkers 11 continuously performing a pushing action is allowing the yarn-pushing surface 115 to push the bottom yarn 31, so as to change the position of the bottom yarn 31 relative to the facing yarn 30 until the hook 121 of one of the plurality of needles 12 is hooked.
Accordingly, the weft knitting machine performs position change at the position where the facing yarn 30 and the bottom yarn 31 are fed into the hook to perform jacquard knitting. Compared with the conventional, the yarn changing reaction time of the weft knitting machine 10 is real-time, and the problem that patterns of a fabric appears after image due to slow yarn changing reaction speed of the conventional can be solved.

Claims

A weft knitting machine (10) capable of changing yarn positions, and capable of feeding a facing yarn (30) and a bottom yarn (31) during knitting, the weft knitting machine (10) comprising:
a plurality of sinkers (11) respectively comprising a belly (111), a nose (112) connected with the belly (111), and a throat (113) between the belly (111) and the nose (112), wherein each of the plurality of sinkers (11) is guided to perform a linear displacement movement (116), so as to position the facing yarn (30) above the nose (112) and the bottom yarn (31) in the throat (113) during a process of the linear displacement movement (116); and

a plurality of needles (12) respectively arranged adjacent to one of the plurality of sinkers (11), a motion direction of plurality of needles (12) perpendicular to a direction of the linear displacement movement (116), each of the plurality of needles (12) including a hook (121) and a latch (122) for performing a closing action relative to the hook (121),

characterised in that in a first needle retracting track (40), each of the plurality of needles (12) controls the latch (122) performing a closing action at a first latch closing time point; and in a second needle retracting track (41), each of the plurality of needles (12) controls the latch (122) performing a closing action at a second latch closing time point before the first latch closing time point;

wherein each of the plurality of needles (12) in the first needle retracting track (40) can knit a standard plating without changing positions of the facing yarn (30) and the bottom yarn (31) in the hook (121); and

wherein each of the plurality of needles (12) in the second needle retracting track (41) knits an interchanged plating with changing the positions of the facing yarn (30) and the bottom yarn (31) in the hook (121), wherein in the second needle retracting track (41), the latch (122) is capable to drive the bottom yarn (31) to make the bottom yarn (31) pushed by the nose (112) of one of the plurality of sinkers (11) when one of the plurality of sinkers (11) adjacent to each of the plurality of needles (12) does not restrict positions of the facing yarn (30) and the bottom yarn (31).
The weft knitting machine (10) with changeable yarn positions according to claim 1, wherein the weft knitting machine (10) comprises a needle guide plate (14) comprising the first needle retracting track (40) and the second needle retracting track (41) to guide the plurality of needles (12), and a sinker guide plate (13) guiding the plurality of sinkers (11) to perform the linear displacement movement (116).
The weft knitting machine (10) with changeable yarn positions according to claim 2, wherein the weft knitting machine (10) comprises a needle selector controlling each of the plurality of needles (12).
The weft knitting machine (10) with changeable yarn positions according to claim 1, 2 or 3, wherein each of the plurality of sinkers (11) only moves in one motion track (42) that recurring operations of a first retraction section (421), a first push-out section (422) subsequent to the first retraction section (421), a second retraction section (423) subsequent to the first push-out section (422), and a second push-out section (424) subsequent to the second retraction section (423), and wherein the time point for the latch (122) of each of the plurality of needles (12) generating the closing action in the first needle retracting track (40) is that one of the plurality of sinkers (11) adjacent to the latch (122) moves to the second retraction section (423), and the time point for the latch (122) of each of the plurality of needles (12) generating the closing action in the second needle retracting track (41) is that one of the plurality of sinkers (11) adjacent to the latch (122) moves to the first push-out section (422).