Yarn feeding device of flatbed knitting machine

Abstract

 A yarn feeding device (1) of a flatbed knitting machine includes a yarn feeding arm (12) that extends downward from a base that slides along a travel rail, the yarn feeding arm (12) being connected to a plaiting-yarn feeding port (14); a swing arm (2) that is supported so as to be swingable in front and back directions with respect to the yarn feeding arm (12), the swing arm (2) having the plaiting-yarn feeding port (14) at a lower end portion; a shift member (31) supported so as to be vertically slidable with respect to the yarn feeding arm (12); and shift operation means (37) for shifting the plaiting-yarn feeding port (14) between a reference position and a front or back position using the swing arm (2) in accordance with a vertical slide of the shift member (31).

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The present invention relates to a yarn feeding device of a flatbed knitting machine, and more specifically, to a yarn feeding device in which a knitting needle enables reliable yarn catching when the knitting yarn is fed to the knitting needle.

2. Description of the Related Art

[0002] A yarn feeding device of a flatbed knitting machine includes a single yarn feeding arm that extends downward from a base that slides along a travel rail. The yarn feeding arm has a yarn feeding port (for example, see Patent Literature 1). The knitting yarn is fed through the yarn feeding port to a hook of a knitting needle that has entered a needle bed gap from a front or back needle bed by being placed on a passage along which the hook retracts. The knitting yarn is caught by the hook of the knitting needle when the knitting needle retracts.

[0003] Patent Literature 1: Japanese Unexamined Patent Application Publication No. 5-25758

[0004] In some cases, however, placing the knitting yarn fed through the yarn feeding port on the passage along which the hook that has entered the needle bed gap retracts is difficult depending on the way of knitting.

[0005] A case is described as an example where a pattern is to be knitted in the middle of a fabric in such a manner that stitches are missed between knitted stitches in a single knitting course. In this case, at the transition from the stitch missing to knitting, the knitting yarn fed through the yarn feeding port is more likely to be placed at a position higher than the passage along which the hook retracts. This operation is more likely to cause the knitting yarn to be deviated from the passage along which the hook of the knitting needle that has arrived at the needle bed gap retracts, whereby the knitting needle may fail in reliable yarn catching.

SUMMARY OF THE INVENTION

[0006] Accordingly, it is an object of the present invention to provide a yarn feeding device of a flatbed knitting machine in which a knitting needle enables reliable yarn catching.

[0007] In order to achieve the above object, the present invention provides a yarn feeding device of a flatbed knitting machine that includes a yarn feeding arm that extends downward from a base supported so as to be slidable along a travel rail, the yarn feeding arm being connected to a yarn feeding port, a swing arm that is supported so as to be swingable in front and back directions of a needle bed (the directions are simply referred to as front and back directions, below) with respect to the yarn feeding arm, the front and back directions of the needle bed corresponding to front and back directions of the yarn feeding arm, the swing arm having the yarn feeding port at a lower end portion, and a shift mechanism that is capable of shifting the yarn feeding port with respect to the yarn feeding arm between a reference position and a front or back position using the swing arm.

[0008] The shift mechanism may include a shift member supported so as to be vertically slidable with respect to the yarn feeding arm, and shift operation means for shifting the yarn feeding port between the reference position and the front or back position in accordance with a vertical slide of the shift member.

[0009] The shift operation means may include a support member that is disposed on a lower end portion of the shift member and supports a vertically middle portion of the swing arm so that the vertically middle portion is vertically slidable, the swing arm having an upper end attached to the yarn feeding arm, and a slope portion that is disposed on the yarn feeding arm to guide the support member so that the support member slides in front and back directions. In addition, the yarn feeding port may be shifted between the reference position and the front or back position together with the support member while the support member is being guided so as to slide along the slope portion by the vertical slide of the shift member.

[0010] Alternatively, the shift operation means includes an insertion hole that is open at a lower end portion of the shift member, the insertion hole allowing a vertically middle portion of the swing arm to be inserted therethrough so as to exert a frontward and backward bending force on the swing arm together with the yarn feeding arm, the swing arm having an upper end attached to the yarn feeding arm, and a support pin disposed on a lower end portion of the yarn feeding arm to reverse the frontward and backward bending force exerted on the swing arm. The yarn feeding port may be shifted between the reference position and the front or back position as a result of the support pin reversing the frontward and backward bending force exerted on the swing arm in accordance with the vertical slide of the shift member.

[0011] The yarn feeding port may include a plaiting-yarn feeding port, through which a plaiting yarn is fed during plaiting, in addition to a main-yarn feeding port, through which a main yarn is fed during plaiting.

[0012] The yarn feeding device also includes a decentering mechanism that rotates with respect to the swing arm around a horizontal axis extending in front and back directions of the swing arm, the decentering mechanism including a decentering member that includes a decentered shaft portion that is decentered with respect to the horizontal axis. The plaiting-yarn feeding port may be located above the main-yarn feeding port and may be capable of being vertically brought close to or spaced apart from the main-yarn feeding port using the decentered shaft portion.

[0013] Even though a knitting yarn fed through the yarn feeding port is placed at a higher position with respect to a passage along which a hook of a knitting needle that has entered a needle bed gap retracts, the knitting yarn can be more easily placed on the passage along which the hook retracts by swinging the feeding port between the reference position and the front or back position using the swing arm when the shift mechanism shifts the yarn feeding arm. Thus, the knitting needle enables reliable yarn catching.

[0014] The yarn feeding port is shifted between the reference position and the front or back position in accordance with the vertical slide of the shift member with respect to the yarn feeding arm, whereby shifting of the yarn feeding port is facilitated.

[0015] The yarn feeding port is shifted between the reference position and the front or back position together with the support member while the support member is being guided so as to slide along the slope portion in accordance with the vertical slide of the shift member, whereby the yarn feeding port can be reliably shifted.

[0016] Alternatively, the yarn feeding port is shifted between the reference position and the front or back position as a result of the support pin reversing the frontward and backward bending force exerted on the swing arm in accordance with the vertical slide of the shift member, whereby the yarn feeding port can be reliably shifted.

[0017] Applying the present invention to a plaiting-yarn feeding port through which a plaiting yarn is fed during plaiting has the following advantages. The plaiting yarn placed higher than the main yarn is more likely to be placed on the passage along which a hook of a knitting needle that has entered a needle bed gap retracts, whereby the knitting needle enables reliable yarn catching. In addition, the plait caught by the knitting needle is always brought to the inner side of the hook than the main yarn. Thus, the positions of the plaiting yarn and the main yarn are not inverted, whereby color mixture in the knitted fabric that would occur due to the inversion of the plaiting yarn can be reliably prevented.

[0018] In addition, the decentering mechanism vertically moves a coupling board, having the plaiting-yarn feeding port at the lower end, with respect to the shaft portion in the vertically long hole in accordance with the lateral movement of the decentered shaft portion in the laterally long hole due to the rotation of the decentering member around the horizontal axis. The decentering mechanism also causes the coupling board to vertically slide with respect to the yarn feeding arm. Thus, the vertical position of the plaiting-yarn feeding port can be smoothly adjusted by rotation of the decentering member. In this manner, a gap between the main yarn and the plaiting yarn fed to the knitting needle or the angle at which the main yarn or the plaiting yarn is fed to the knitting needle can be finely adjusted in accordance with different conditions such as the thickness, the type, or the knitting conditions of the main yarn or the plait.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] 

Fig. 1 is a front view of a yarn feeding device of a flatbed knitting machine according to a first embodiment of the present invention;

Figs. 2A to 2D are cross-sectional views of the yarn feeding device taken along the line A-A of Fig. 1, where Fig. 2A illustrates a state where a plaiting-yarn feeding port brought close to a main-yarn feeding port is shifted to a reference position, Fig. 2B illustrates a state where the plaiting-yarn feeding port brought close to the main-yarn feeding port is shifted to a back position, Fig. 2C illustrates a state where the plaiting-yarn feeding port spaced apart from the main-yarn feeding port is shifted to the reference position, and Fig. 2D illustrates a state where the plaiting-yarn feeding port spaced apart from the main-yarn feeding port is shifted to the back position;

Figs. 3A and 3B illustrate the states where a latch needle that has entered a needle bed gap from the front needle bed catches the main yarn fed through the main-yarn feeding port of the yarn feeding device illustrated in Fig. 1 and the plaiting yarn fed through the plaiting-yarn feeding port of the yarn feeding device, where Fig. 3A illustrates the state where the hook of the latch needle has entered the needle bed gap and Fig. 3B illustrates the state where the hook of the latch needle starts retracting;

Fig. 4 is a vertical-sectional view of a decentering member of the yarn feeding device illustrated in Fig. 1 when viewed from the side;

Fig. 5 is a front view of a portion of a yarn feeding device of a flatbed knitting machine according to a second embodiment of the present invention, the portion being near a yarn feeding arm;

Figs. 6A to 6D are cross-sectional views of the yarn feeding device taken along the line B-B of Fig. 5, where Fig. 6A illustrates the state where the plaiting-yarn feeding port brought close to the main-yarn feeding port is shifted to the reference position, Fig. 6B illustrates the state where the plaiting-yarn feeding port brought close to the main-yarn feeding port is shifted to the back position, Fig. 6C illustrates the state where the plaiting-yarn feeding port spaced apart from the main-yarn feeding port is shifted to the reference position, and Fig. 6D illustrates the state where the plaiting-yarn feeding port spaced apart from the main-yarn feeding port is shifted to the back position;

Fig. 7 is a front view of a portion of a yarn feeding device of a flatbed knitting machine according to a third embodiment of the present invention, the portion being near a yarn feeding arm; and

Figs. 8A to 8D are cross-sectional views of the yarn feeding device taken along the line C-C, where Fig. 8A illustrates the state where the plaiting-yarn feeding port brought close to the main-yarn feeding port is shifted to the reference position, Fig. 8B illustrates the state where the plaiting-yarn feeding port brought close to the main-yarn feeding port is shifted to the back position, Fig. 8C illustrates the state where the plaiting-yarn feeding port spaced apart from the main-yarn feeding port is shifted to the reference position, and Fig. 8D illustrates the state where the plaiting-yarn feeding port spaced apart from the main-yarn feeding port is shifted to the back position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Referring to the drawings, embodiments of the present invention will be described below.

[0021] Fig. 1 is a front view of a yarn feeding device 1 of a flatbed knitting machine according to a first embodiment of the present invention. Figs. 2A to 2D are cross-sectional views of the yarn feeding device 1 taken along the line A-A of Fig. 1, where Fig. 2A illustrates a state where a plaiting-yarn feeding port 14 brought close to a main-yarn feeding port 13 is shifted to a reference position, Fig. 2B illustrates a state where the plaiting-yarn feeding port 14 brought close to the main-yarn feeding port 13 is shifted to a back position, Fig. 2C illustrates a state where the plaiting-yarn feeding port 14 spaced apart from the main-yarn feeding port 13 is shifted to the reference position, and Fig. 2D illustrates a state where the plaiting-yarn feeding port 14 spaced apart from the main-yarn feeding port 13 is shifted to the back position.

[0022] A yarn feeding device 1 illustrated in Figs. 1 and Fig. 2A to 2D performs plaiting and includes a base 11 and a single yarn feeding arm 12. The base 11 slides along a travel rail extending parallel to the direction in which a carriage, not illustrated, travels. The yarn feeding arm 12 is attached to a lower end portion of a flange piece 111 extending downward from the base 11. The yarn feeding arm 12 is connected to both a main-yarn feeding port 13 and a plaiting-yarn feeding port 14 located above the main-yarn feeding port 13. A lower end portion of the yarn feeding arm 12 is bifurcated into left and right pieces 15 that extend downward. To the outer edge of each bifurcated piece 15, an upper end portion of a substantially V-shaped main-yarn feeding guide 16 is coupled. The main-yarn feeding port 13 is open at the lower end of a main-yarn eyelet 161 that vertically extends through a joint of the main-yarn feeding guide 16. The yarn feeding arm 12 is fastened to the base 11 using a screw that is inserted into a vertical hole, whereby the vertical position of the main-yarn feeding port 13 is made adjustable.

[0023] The yarn feeding device 1 includes a swing arm 2 and a shift mechanism 3. The swing arm 2 is supported so as to be swingable in front and back directions of a needle bed, corresponding to front and back directions of the yarn feeding arm 12. The shift mechanism 3 is capable of shifting the swing arm 2 with respect to the yarn feeding arm 12 so that a lower end portion of the swing arm 2 is shifted between the reference position (illustrated in Fig. 2A and 2C) and the back position (illustrated in Fig. 2B and 2D). Here, the reference position is the position at which the plaiting-yarn feeding port 14 coincides with the main-yarn feeding port 13 in the front and back directions when viewed from the side. The back position is the position at which the plaiting-yarn feeding port 14 is spaced most distant from the main-yarn feeding port 13 in the back direction. The back position includes positions located backward of the reference position but nearer to the reference position than the back position illustrated in Figs. 2B and 2D.

[0024] The shift mechanism 3 includes a shift member 31 supported so as to be vertically swingable with respect to the yarn feeding arm 12. The shift member 31 has a long hole 32, which is long in the vertical direction, at an upper end portion. The shift member 31 includes a pair of left and right bifurcated pieces 33 that are bifurcated to the left and right at a substantially middle portion of the shift member 31 and that extend downward so as to be substantially parallel to each other. An upper end portion of the shift member 31 is fastened to a portion of the yarn feeding arm 12 on the left or right side (left side in Fig. 1) using a bolt 34, inserted into the long hole 32, and a nut 35. A handle piece 36 is disposed on the upper end of the shift member 31 so as to protrude frontward (to the near side of Fig. 1).

[0025] The swing arm 2 is coupled, using a coupler 21, to a lower end portion of a coupling member 20 supported so as to be swingable in the vertical direction at a portion of the yarn feeding arm 12 on the left or right side (right side in Fig. 1) on the surface of the yarn feeding arm 12. The coupling member 20 has a long hole 22, which is long in the vertical direction, at the lower end portion of the coupling member 20. The coupling member 20 is screwed to an upper portion of the coupler 21 using the screw member 23 inserted into the long hole 22. The coupler 21 has guide grooves 211 on the upper left and right end portions. The guide grooves 211 guide the bifurcated pieces 33 of the shift member 31 by holding the bifurcated pieces 33 from the front and back directions so that the bifurcated pieces 33 are slidable in the vertical direction. The coupler 21 has a hole portion 212, which is open downward, at a lower portion of the coupler 21. An upper end portion of the swing arm 2 is inserted into the hole portion 212 so that the swing arm 2 is fixed to the coupler 21 using a pin 213 extending in the left and right directions. A plaiting-yarn feeding guide 24 is disposed at the lower end of the swing arm 2. The plaiting-yarn feeding port 14 is open at the lower end of the plaiting-yarn eyelet 25 that vertically extends through the plaiting-yarn feeding guide 24.

[0026] The shift mechanism 3 also includes shift operation means 37 for shifting the plaiting-yarn feeding port 14 at the lower end of the swing arm 2 between the reference position and the back position in accordance with a vertical slide of the shift member 31. The shift operation means 37 includes a support member 38 and slope portions 39. The support member 38 is disposed at a lower end portion of the shift member 31 to support a vertically middle portion of the swing arm 2 in such a manner that the vertically middle portion is vertically slidable. The slope portions 39 are disposed at portions of the bifurcated pieces 15 of the yarn feeding arm 12 in substantially the middle in the vertical direction to guide left and right end portions of the support member 38 in such a manner that the left and right end portions slide over the slope portions 39 in the front and back directions. The upper and lower surfaces of the slope portion 39 are inclined so as to be located further backward toward the lower side. The support member 38 has grooves 381 along the slope portions 39 on the left and right end portions. The support member 38 is guided so as to slide over the slope portions 39 in accordance with the vertical slide of the shift member 31.

[0027] Figs. 3A and 3B illustrate the states where a latch needle 55 that has entered a needle bed gap 50 from a front needle bed catches a main yarn 51 fed through the main-yarn feeding port 13 of the yarn feeding device 1 and a plaiting yarn 52 fed through the plaiting-yarn feeding port 14 of the yarn feeding device 1, where Fig. 3A illustrates the state where a hook 56 of the latch needle 55 has entered the needle bed gap 50 and Fig. 3B illustrates the state where the hook 56 of the latch needle 55 starts retracting. Fig. 3A illustrates the state where plaiting is performed using a main yarn 51 fed through the main-yarn feeding port 13 and a plaiting yarn 52 fed through the plaiting-yarn feeding port 14. In the case where stitches are missed between knitted stitches in a single knitting course, at the transition from the stitch missing to knitting, the plaiting yarn 52 fed through the plaiting-yarn feeding port 14 is placed at a position (position drawn by a two-dot chain line) higher than the passage along which the hook 56 of the latch needle 55 that has entered the needle bed gap 50 from the front needle bed retracts. The lines indicated by 50a in Figs. 3A and 3B represent the center of the needle bed gap 50.

[0028] At this time, the coupling member 20 and the shift member 31 are bent in the front and back directions and elastically deformed, whereby the plaiting-yarn feeding port 14 is shifted from the reference position to the back position. Thus, the plaiting-yarn feeding port 14 can be easily shifted to the back position together with the downward sliding movement of the shift member 31. The plaiting yarn 52 fed through the plaiting-yarn feeding port 14 is consequently moved to the position drawn with the solid line from the position drawn with the two-dot chain line illustrated in Fig. 3A. The plaiting yarn 52 is thus more likely to be placed on the passage along which the hook 56 that has entered the needle bed gap 50 retracts, whereby the latch needle 55 enables reliable yarn catching. As illustrated in Fig. 3B, the plaiting yarn 52 caught by the latch needle 55 is always brought to the inner side of the hook 56 than the main yarn 51. Thus, the positions of the plaiting yarn 52 and the main yarn 51 are not inverted, whereby color mixture in the knitted fabric that would occur due to the inversion of the plaiting yarn 52 can be reliably prevented.

[0029] In this embodiment, a latch needle 55 is used as a knitting needle, but a compound needle is also naturally usable as a knitting needle.

[0030] One of the bifurcated pieces 15 of the yarn feeding arm 12 has a scale 19 on its inner edge to indicate the distance by which the shift member 31 slides in the vertical direction. The scale 19 is a protruding piece that includes three protrusions arranged side by side and protruding from the inner edge of the bifurcated piece 15. One of the bifurcated pieces 33 of the shift member 31 includes a substantially triangular indicator 331 protruding toward the inner edge of the bifurcated piece 15 including the scale 19. On the basis of the position of the scale 19 indicated by the indicator 331, the distance by which the shift member 31 has vertically slid is visually indicated.

[0031] Fig. 4 is a vertically-sectional view of a decentering member of the yarn feeding device 1 when viewed from the side. In Fig. 4, a decentering mechanism 4 including a decentering member 41 is disposed above the coupling member 20. The decentering member 41 rotates around the horizontal axis m extending in the front and back directions at a portion of the yarn feeding arm 12 on the left or right side opposite to the side on which the shift member 31 is disposed. The decentering member 41 has a decentered axis n that is decentered with respect to the horizontal axis m. The decentering member 41 includes a horizontal shaft portion 42 having a center on the horizontal axis m and a decentered shaft portion 43 having a center on the decentered axis n. The coupling member 20 is disposed so as to be capable of being vertically shifted with respect to the yarn feeding arm 12 with the decentered shaft portion 43 of the decentering member 41 interposed therebetween. The plaiting-yarn feeding port 14 connected to the lower end portion of the swing arm 2 can be vertically brought close to or spaced apart from the main-yarn feeding port 13. Thus, the position at which the plaiting yarn 52 fed through the plaiting-yarn feeding port 14 is placed is vertically changed by the decentering mechanism 4. Moreover, a vertical gap between the main yarn 51 fed to the latch needle 55 through the main-yarn feeding port 13 and the plaiting yarn 52 fed to the latch needle 55 through the plaiting-yarn feeding port 14 or the angle at which the main yarn 51 or the plaiting yarn 52 is fed to the latch needle 55 can be finely adjusted in accordance with different conditions such as the thickness, the type, or the knitting conditions of the main yarn 51 or the plaiting yarn 52.

[0032] The horizontal shaft portion 42 includes a wide diameter portion 421, held in a space between the yarn feeding arm 12 and the coupling member 20, and a head portion 422, which protrudes from the back surface (right side in Fig. 4) of the wide diameter portion 421 so as to be integrated with the wide diameter portion 421. The head portion 422 has a hexagonal hole at the end portion that protrudes from the back surface of the yarn feeding arm 12. The head portion 422 is inserted into a hole portion 122 formed in the yarn feeding arm 12. The decentered shaft portion 43 protrudes from the surface (left side in Fig. 4) of the wide diameter portion 421 so as to be integrated with the wide diameter portion 421.

[0033] The decentering mechanism 4 also includes a screw-fix member 44 that fixes the coupling member 20 to the yarn feeding arm 12 by screwing. The screw-fix member 44 includes a screw member 442 and a stepped nut member 443. The screw member 442 includes a shaft portion 441 that extends parallel to the decentered axis n and that is inserted from the surface side of the yarn feeding arm 12. The stepped nut member 443 is inserted into the insertion hole 121 of the yarn feeding arm 12 from the back surface side and screwed on a top end portion of the shaft portion 441. The insertion hole 121 has the same shape as a rectangular step portion 444 and restrains the stepped nut member 443 from rotating with respect to the yarn feeding arm 12. Fig. 4 also illustrates a washer 45 disposed between the screw member 442 and the coupling member 20.

[0034] The decentering mechanism 4 also includes a vertically long hole 47, which is long in the vertical direction, above the coupling member 20 and a laterally long hole 46, which is long in the lateral direction, below the vertically long hole 47. The decentered shaft portion 43 has an annular groove 431 and is inserted and held in the laterally long hole 46. The annular groove 431 is exposed from the surface of the coupling member 20 when the decentered shaft portion 43 is inserted into the laterally long hole 46. A fastener 432 is fitted to the annular groove 431 to fix the decentered shaft portion 43 to the coupling member 20 so that the decentered shaft portion 43 does not come off. The decentered shaft portion 43 laterally moves in the laterally long hole 46 in accordance with a rotation of the decentering member 41 around the horizontal axis m. The shaft portion 441 of the screw member 442 is inserted and held in the vertically long hole 47. When the screw-fix member 44 is loosened and the decentering member 41 is rotated around the horizontal axis m, the decentered shaft portion 43 laterally moves in the laterally long hole 46. Accordingly, the coupling member 20 is vertically moved in the vertically long hole 47 with respect to the shaft portion 441 of the screw member 442. In this manner, the vertical position of the plaiting-yarn feeding port 14 can be smoothly adjusted by the rotation of the decentering member 41.

[0035] To the flange piece 111 of the base 11, a yarn guide support 54 is also attached. The yarn guide support 54 includes five yarn guides 53 that each guide the main yarn 51 or the plaiting yarn 52 paid out from a tension device, not illustrated, to the main-yarn feeding port 13 or the plaiting-yarn feeding port 14. Here, any yarn guide 53 is naturally usable to guide the main yarn 51 or the plaiting yarn 52 paid out from a tension device to the main-yarn feeding port 13 or the plaiting-yarn feeding port 14.

[0036] Referring now to Figs. 2A to 2D, the way how the shift mechanism 3 shifts the plaiting-yarn feeding port 14 to the back position is described together with the way how the decentering mechanism 4 vertically moves the plaiting-yarn feeding port 14.

[0037] In order that the shift mechanism 3 shifts the plaiting-yarn feeding port 14 to the reference position, firstly, the bolt 34 is loosened and the shift member 31 is caused to slide to the topmost position within a movable range limited by the long hole 32 as illustrated in Fig. 2A. Accordingly, the support member 38 arrives at upper end portions of the slope portions 39, which are inclined further forward as they come closer to the top, and the plaiting-yarn feeding port 14 at the lower end of the swing arm 2 is shifted to the reference position.

[0038] On the other hand, in order that the shift mechanism 3 shifts the plaiting-yarn feeding port 14 to a back position, the bolt 34 is loosened and the shift member 31 is caused to slide to the lowermost position within a movable range limited by the long hole 32 as illustrated in Fig. 2B. Accordingly, the support member 38 arrives at lower end portions of the slope portions 39, which are inclined further backward as they come closer to the bottom, and the plaiting-yarn feeding port 14 is shifted to the back position. Here, as illustrated in Figs. 2A and 2B, the plaiting-yarn feeding port 14 is brought closest to the main-yarn feeding port 13 as a result of the decentering mechanism 4 rotating the decentering member 41 around the horizontal axis m in a first direction and the coupling member 20 being moved downward within a movable range limited by the vertically long hole 47 with respect to the shaft portion 441 of the screw member 442. Here, by stopping the shift member 31 in the middle of the long hole 32 and fastening the shift member 31 with the bolt 34, the plaiting-yarn feeding port 14 can be shifted to any position between the reference position and the back position.

[0039] In order that the decentering mechanism 4 moves, upward, the plaiting-yarn feeding port 14 shifted to the reference position by the shift mechanism 3, the screw-fix member 44 is loosened and the decentering member 41 is rotated around the horizontal axis m in a second direction. Thus, as illustrated in Fig. 2C, the coupling member 20 is moved upward within a movable range limited by the vertically long hole 47 with respect to the shaft portion 441 of the screw member 442, so that the plaiting-yarn feeding port 14 is spaced most distant from the main-yarn feeding port 13.

[0040] On the other hand, in order that the shift mechanism 3 shifts, from the reference positon to a back position, the plaiting-yarn feeding port 14 that is spaced most distant from the main-yarn feeding port 13 by the decentering mechanism 4, the bolt 34 is loosened and the shift member 31 is caused to slide to the lowermost position within a movable range limited by the long hole 32 as illustrated in Fig. 2D. Accordingly, the support member 38 arrives at lower end portions of the slope portions 39 and the plaiting-yarn feeding port 14 is shifted to the back position.

[0041] Referring now to Fig. 5 and Figs. 6A to 6D, a second embodiment of the present invention will be described.

[0042] Fig. 5 is a front view of a portion of a yarn feeding device of a flatbed knitting machine according to a second embodiment of the present invention, the portion being near a yarn feeding arm. Figs. 6A to 6D are cross-sectional views of the yarn feeding device taken along the line B-B of Fig. 5, where Fig. 6A illustrates the state where a plaiting-yarn feeding port 19 brought close to a main-yarn feeding port 86 is shifted to the reference position, Fig. 6B illustrates the state where the plaiting-yarn feeding port 19 brought close to the main-yarn feeding port 86 is shifted to the back position, Fig. 6C illustrates the state where the plaiting-yarn feeding port 19 spaced apart from the main-yarn feeding port 86 is shifted to the reference position, and Fig. 6D illustrates the state where the plaiting-yarn feeding port 19 spaced apart from the main-yarn feeding port 86 is shifted to the back position. This embodiment only describes the configuration of a shift mechanism 6.

[0043] As illustrated in Fig. 5 and Figs. 6A to 6D, a shift mechanism 6 includes a shift member 61 and shift operation means 63. The shift member 61 is supported so as to be vertically slidable with respect to the yarn feeding arm 17. The shift operation means 63 shifts a plaiting-yarn feeding port 19 between the reference position and the back position in accordance with a downward sliding movement of the shift member 61. A swing arm 62 includes a pair of left and right bifurcated pieces 66 that are bifurcated to the left and right at a substantially middle portion of the swing arm 62 and that extend downward so as to be substantially parallel to each other. A plaiting-yarn feeding guide 18 is disposed on a lower end portion of each bifurcated piece 66. Also in this case, the reference position and the back position of the plaiting-yarn feeding port 19 are determined in a similar manner as in the case of the first embodiment.

[0044] The shift member 61 has a vertically long hole 611, which is long in the vertical direction, at an upper end portion. The swing arm 62 has a vertically long hole 621, which is long in the vertical direction, at an upper end portion. The shift member 61 and the swing arm 62 are supported by the yarn feeding arm 17 while having a shaft portion 105 of a screw member 104 of a screw-fix member 100 of the decentering mechanism 10 being inserted into the vertically long holes 611 and 621. The shift member 61 has an insertion long hole 612, which is long in the vertical direction. The insertion long hole 612 allows a horizontal shaft portion 102 of the decentering member 101 of the decentering mechanism 10 to be inserted therethrough. The swing arm 62 has a laterally long hole 622 that allows a decentered shaft portion 103 of the decentering member 101 to be inserted therethrough. A lower end portion of the yarn feeding arm 17 is bifurcated into left and right pieces 84 that extend downward. To an inner edge at the lower end of each bifurcated piece 84, an upper end portion of a substantially V-shaped main-yarn feeding guide 85 is coupled. A main-yarn feeding port 86 is open at the lower end of a main-yarn eyelet 851 that vertically extends through a joint of the main-yarn feeding guide 85. On the other hand, a plaiting-yarn feeding port 19 is open at the lower end of a plaiting-yarn eyelet 181 that vertically extends through a plaiting-yarn feeding guide 18. As illustrated in Figs. 6A to 6D, the decentered shaft portion 43 has an annular groove 106 and a fastener 107 is fitted into the annular groove 106. Also as illustrated in Figs. 6A to 6D, a stepped nut member 108 is screwed on a top end portion of a shaft portion 105.

[0045] The shift operation means 63 includes a rectangular hole 64, which is an insertion hole that is open at a lower end portion of the shift member 61. The rectangular hole 64 allows a vertically middle portion of the swing arm 62 to be inserted therethrough so as to bend the vertically middle portion of the swing arm 62 backward (downward in Figs. 6A to 6D) together with the yarn feeding arm 17 to elastically deform the swing arm 62. The shift operation means 63 also includes a pair of left and right support pins 65 at the lower end portions of the bifurcated pieces 84 to support a vertically middle portion of the plaiting-yarn feeding guide 18 from the left and right sides. Each support pin 65 reverses a backward bending force exerted on the swing arm 62 and causes the plaiting-yarn feeding port 19 to swing in the front and back directions in accordance with the bending force. Here, when the shift member 61 slides downward, the backward bending force exerted on the swing arm 62 is reduced in accordance with the sliding. The reduction of the bending force shifts the swing arm 62 forward. Each support pin 65 reverses the bending force of the swing arm 62 that is shifted forward. Thus, the plaiting-yarn feeding port 19 can be reliably shifted from the reference position (illustrated in Figs. 6A and 6C) to the back position (illustrated in Figs. 6B and 6D).

[0046] Referring now to Figs. 6A to 6D, the way how the shift mechanism 6 shifts the plaiting-yarn feeding port 19 to the back position is described together with the way how the decentering mechanism 4 vertically moves the plaiting-yarn feeding port 19.

[0047] In order that the shift mechanism 6 shifts the plaiting-yarn feeding port 19 to the reference position, firstly, the screw member 104 is loosened and the shift member 61 is caused to slide to the topmost position within a movable range limited by the long hole 611 with respect to the shaft portion 105 as illustrated in Fig. 6A. At this time, since a relatively large backward bending force is exerted on the swing arm 62, the plaiting-yarn feeding port 19 at the lower end of the plaiting-yarn feeding guide 18 that has been reversed by each support pin 65 is shifted to the reference position.

[0048] On the other hand, in order that the shift mechanism 6 shifts the plaiting-yarn feeding port 19 to the back position, the screw member 104 is loosened and the shift member 61 is caused to slide to the lowermost position within a movable range limited by the long hole 611 with respect to the shaft portion 105 as illustrated in Fig. 6B. Then, the backward bending force exerted on the swing arm 62 in the rectangular hole 64 is accordingly reduced. This reduced bending force that shifts the swing arm 62 forward is reversed at each support pin 65, so that the plaiting-yarn feeding port 19 is shifted to the back position. At this time, as illustrated in Figs. 6A and 6B, the decentering mechanism 10 rotates the decentering member 101 around the horizontal axis m in a first direction and the swing arm 62 is moved downward within a movable range limited by the vertically long hole 621 with respect to the shaft portion 105 of the screw member 104. Thus, the plaiting-yarn feeding port 19 is brought closest to the main-yarn feeding port 86. Here, by stopping the shift member 61 in the middle of the long hole 611 with respect to the shaft portion 105 and fastening the shift member 61 with a screw member 104, the plaiting-yarn feeding port 19 can be shifted to any position between the reference position and the back position.

[0049] In order that the decentering mechanism 10 moves, upward, the plaiting-yarn feeding port 19 that is shifted to the reference position, the screw member 104 is loosened and the decentering member 101 is rotated around the horizontal axis m in a second direction. Thus, as illustrated in Fig. 6C, the swing arm 62 is moved upward in the vertically long hole 621 with respect to the shaft portion 105 of the screw member 104, so that the plaiting-yarn feeding port 19 is spaced most distant from the main-yarn feeding port 86.

[0050] On the other hand, in order that the shift mechanism 6 shifts, to the back position, the plaiting-yarn feeding port 19 that is spaced most distant from the main-yarn feeding port 86 by the decentering mechanism 10, the screw member 104 is loosened and the shift member 61 is caused to slide to the lowermost position within a movable range limited by the long hole 611 with respect to the shaft portion 105 as illustrated in Fig. 6D. Accordingly, the backward bending force exerted on the swing arm 62 in the rectangular hole 64 is reduced and this reduced bending force that shifts the swing arm 62 forward is reversed at each support pin 65, so that the plaiting-yarn feeding port 19 is shifted to the back position.

[0051] Referring now to Fig. 7 and Figs. 8A to 8D, a third embodiment of the present invention is described.

[0052] Fig. 7 is a front view of a portion of a yarn feeding device of a flatbed knitting machine according to a third embodiment of the present invention, the portion being near a yarn feeding arm 87. Figs. 8A to 8D are cross-sectional views of the yarn feeding device taken along the line C-C of Fig. 7, where Fig. 8A illustrates the state where a plaiting-yarn feeding port 93 brought close to a main-yarn feeding port 92 is shifted to the reference position, Fig. 8B illustrates the state where the plaiting-yarn feeding port 93 brought close to the main-yarn feeding port 92 is shifted to the back position, Fig. 8C illustrates the state where the plaiting-yarn feeding port 93 spaced apart from the main-yarn feeding port 92 is shifted to the reference position, and Fig. 8D illustrates the state where the plaiting-yarn feeding port 93 spaced apart from the main-yarn feeding port 92 is shifted to the back position. This embodiment only describes the configuration of the shift mechanism.

[0053] As illustrated in Fig. 7 and Figs. 8A to 8D, a yarn feeding arm 87 includes a swing member 72 having an upper end portion supported with a pin 71, extending in the left and right directions, so as to be swingable in the front and back directions. A substantially rectangular hole portion 73 is formed at a lower end portion of the swing member 72. A decentering mechanism 9 is disposed over a vertically middle portion of the swing member 72 with a coupling member 75 interposed therebetween. A swing arm 89 is equipped with a plaiting-yarn feeding guide 88 at a lower end portion. A vertically middle portion of the swing arm 89 is slidably inserted into a through hole 77 that vertically extends through a lower edge portion of the hole portion 73. An upper end portion of the swing arm 89 is drawn out into the hole portion 73 through the through hole 77 and is connected to a lower end portion of the swing member 72 using a coupling member 75 having a lower end portion fastened by a screw 76.

[0054] A shift mechanism 8 is disposed over a vertically middle portion of the swing member 72 to shift a plaiting-yarn feeding port 93 at the lower end of the swing arm 89 between the reference position and the back position. The shift mechanism 8 includes a screw hole 81, a bolt member 82, a nut member 83, and a boss 96. The screw hole 81 is open at a vertically middle portion of the swing member 72. The bolt member 82 has a shaft portion that is screwed in the screw hole 81 and the top end of the shaft portion protrudes from the surface of the swing member 72. The nut member 83 is screwed on the shaft portion of the bolt member 82 from the surface side of the swing member 72 to prevent the bolt member 82 from rotating with respect to the swing member 72. The boss 96 protrudes at the base end of the shaft portion of the bolt member 82. The boss 96 is fastened from the back surface side of the yarn feeding arm 87 using a fastener 95 such as a washer so as not to come off. The swing member 72 is supported by the pin 72 in such a manner that the back surface of the swing member 72 is slightly spaced apart from the surface of the yarn feeding arm 87. When the bolt member 82 is rotated so that the swing member 72 moves counterclockwise with respect to the surface of the yarn feeding arm 87, the swing member 72 approaches the surface of the yarn feeding arm 87 and the swing arm 89 inserted into the through hole 77 is swung backward, so that the plaiting-yarn feeding port 93 is shifted from the reference position to the back position. A lower end portion of the yarn feeding arm 87 is bifurcated into left and right pieces 90 that extend downward. An upper end portion of a substantially V-shaped main-yarn feeding guide 91 is coupled to the outer edge portion of a lower end portion of each bifurcated piece 90. A main-yarn feeding port 92 is open at the lower end of the main-yarn eyelet 911 that vertically extends through a joint of the main-yarn feeding guide 91. On the other hand, a plaiting-yarn feeding port 93 is open at the lower end of a plaiting-yarn eyelet 881 that vertically extends through the plaiting-yarn feeding guide 88. Also in this case, the reference position and the back position of the plaiting-yarn feeding port 93 are determined in a similar manner as in the case of the first embodiment.

[0055] The coupling member 75 includes a vertically long hole 751 and a laterally long hole 752. The vertically long hole 751 allows a shaft portion 902 of a screw member 901 of a screw-fix member 900 of the decentering mechanism 9 screwed on the swing member 72 to be inserted therethrough and held therein. The laterally long hole 752 is formed on the side of the vertically long hole 751 and allows a decentered shaft portion (not illustrated) of a decentering member 903 to be inserted therethrough and held therein.

[0056] Referring now to Figs. 8A to 8D, the way how the shift mechanism 8 shifts the plaiting-yarn feeding port 93 to the back position is described together with the way how the decentering mechanism 9 vertically moves the plaiting-yarn feeding port 93.

[0057] In order that the shift mechanism 8 shifts the plaiting-yarn feeding port 93 to the reference position, firstly, the nut member 83 is loosened and the bolt member 82 is rotated clockwise with respect to the surface of the yarn feeding arm 87 so that the swing member 72 is swung around the pin 71 and separated from the surface of the yarn feeding arm 87 as illustrated in Fig. 8A. Then, the swing arm 89 inserted into the through hole 77 is swung forward and the plaiting-yarn feeding port 93 at the lower end of the plaiting-yarn feeding guide 88 is shifted to the reference position. At this time, the nut member 83 is fastened to the shaft portion of the bolt member 82 so that the bolt member 82 is not rotated with respect to the swing member 72.

[0058] On the other hand, in order that the shift mechanism 8 shifts the plaiting-yarn feeding port 93 to the back position, the nut member 83 is loosened and the bolt member 82 is rotated so that the swing member 72 moves counterclockwise with respect to the surface of the yarn feeding arm 87, so that the swing member 72 is swung around the pin 71 and approaches the surface of the yarn feeding arm 87 as illustrated in Fig. 8B. Then, the swing arm 89 inserted into the through hole 77 is swung backward and the plaiting-yarn feeding port 93 is shifted to the back position. Also at this time, the nut member 83 is fastened to prevent the bolt member 82 from rotating. As illustrated in Figs. 8A and 8B, the decentering mechanism 9 rotates the decentering member 903 around the horizontal axis m in a first direction and the coupling member 75 is moved downward in the vertically long hole 751 with respect to the shaft portion 902 of the screw member 901, so that the plaiting-yarn feeding port 93 is brought closest to the main-yarn feeding port 92. Here, by adjusting the direction in which or the amount by which the bolt member 82 is rotated to adjust the distance between the swing member 72 and the surface of the yarn feeding arm 87, the plaiting-yarn feeding port 93 can be shifted to any position between the reference position and the back position.

[0059] In order that the decentering mechanism 9 shifts, upward, the plaiting-yarn feeding port 93 shifted to the reference position, the screw member 901 is loosened and the decentering member 903 is rotated around the horizontal axis m in a second direction. Thus, the coupling member 75 is moved upward in the vertically long hole 751 with respect to the shaft portion 902 of the screw member 901, so that the plaiting-yarn feeding port 93 is spaced most distant from the main-yarn feeding port 92 as illustrated in Fig. 8C.

[0060] On the other hand, in order that the shift mechanism 8 shifts, from the reference position to the back position, the plaiting-yarn feeding port 93 that is spaced most distant from the main-yarn feeding port 92 by the decentering mechanism 9, the nut member 83 is loosened and the bolt member 82 is rotated counterclockwise with respect to the surface of the yarn feeding arm 87. Thus, the swing member 72 is swung around the pin 71 and approaches the surface of the yarn feeding arm 87 and the swing arm 89 inserted into the through hole 77 is swung backward, so that the plaiting-yarn feeding port 93 is shifted to the back position as illustrated in Fig. 8D.

[0061] Each embodiment has described the case where the shift mechanism 3, 6, or 8 is used for the plaiting-yarn feeding port 14, 19, or 93. However, the shift mechanism may be used for a single yarn feeding port provided for a yarn feeding arm. In this case, even though a knitting yarn fed through the yarn feeding port is placed at a higher position with respect to a passage along which a hook of a knitting needle that has entered a needle bed gap retracts at the transition from stitch missing to knitting, the knitting yarn can be more easily placed on the passage along which the hook retracts, whereby the knitting needle enables reliable yarn catching.

[0062] In each embodiment, the plaiting-yarn feeding port 14, 19, or 93 can be vertically brought close to or spaced apart from the main-yarn feeding port 13, 86, or 92 using the decentered shaft portion 43 or 103 of the decentering mechanism 4, 10, or 9 as well as being shifted by the shift mechanism 3, 6, or 8 between the reference position and the back position. However, the plaiting-yarn feeding port 14, 19, or 93 may only be shifted by the shift mechanism 3, 6, or 8.

[0063] Each embodiment has described the case where the plaiting-yarn feeding port 14, 19, or 93 is shifted between the reference position and the back position, at which the plaiting-yarn feeding port 14, 19, or 93 is spaced most distant from the main-yarn feeding port 13, 86, or 92 in the back direction. However, the present invention is also applicable to the case where the plaiting-yarn feeding port is shifted between the reference position and a position that is spaced apart from the reference position but closer to the reference position than the back position at which the plaiting-yarn feeding port is spaced most distant from the main-yarn feeding port in the back direction. In addition, in order to facilitate placing the plaiting yarn fed through the plaiting-yarn feeding port on the passage along which the hook retracts, the present invention is naturally applicable to the case where the plaiting-yarn feeding port is shifted between the reference position and a front position. In addition, the present invention is also applicable to the case where a plaiting-yarn feeding port provided for a yarn feeding arm provided separately from a yarn feeding arm for which a main-yarn feeding port is provided is shifted between the reference position and a front or back position.

[0064] In each embodiment, the reference position is defined as a position at which the plaiting-yarn feeding port 14, 19, or 93 coincides with the main-yarn feeding port 13, 86, or 92 in the front and back directions when viewed from the side. However, the reference position may be appropriately defined at any position regardless of the cases, such as the case where a single yarn feeding arm is connected to a main-yarn feeding port and a plaiting-yarn feeding port, the case where a yarn feeding arm is connected to a main-yarn feeding port and another yarn feeding arm is connected to a plaiting-yarn feeding port, or the case where a single yarn feeding arm is connected to a single yarn feeding port.

Claims

1. A yarn feeding device (1) of a flatbed knitting machine, comprising:

a yarn feeding arm (12, 17, 87) that extends downward from a base (11) supported so as to be slidable along a travel rail, the yarn feeding arm (12, 17, 87) being connected to a yarn feeding port (14, 19, 93);

a swing arm (2, 62, 89) that is supported so as to be swingable in front and back directions of a needle bed with respect to the yarn feeding arm (12, 17, 87), the front and back directions of the needle bed corresponding to front and back directions of the yarn feeding arm (12, 17, 87), the swing arm (2, 62, 89) having the yarn feeding port (14, 19, 93) at a lower end portion; and

a shift mechanism (3, 6, 8) that is capable of shifting the yarn feeding port (14, 19, 93) with respect to the yarn feeding arm (12, 17, 87) between a reference position and a front or back position using the swing arm (2, 62, 89).

2. The yarn feeding device (1) according to Claim 1,
wherein the shift mechanism (3, 6) includes
a shift member (31, 61) supported so as to be vertically slidable with respect to the yarn feeding arm (12, 17), and
shift operation means (37, 63) for shifting the yarn feeding port (14, 19) between the reference position and the front or back position in accordance with a vertical slide of the shift member (31, 61).

3. The yarn feeding device (1) according to Claim 2,
wherein the shift operation means (37) includes
a support member (38) that is disposed on a lower end portion of the shift member (31) and supports a vertically middle portion of the swing arm (2) so that the vertically middle portion is vertically slidable, the swing arm (2) having an upper end attached to the yarn feeding arm (12), and
a slope portion (39) that is disposed on the yarn feeding arm (12) to guide the support member (38) so that the support member (38) slides in front and back directions, and
wherein the yarn feeding port (14) is shifted between the reference position and the front or back position together with the support member (38) while the support member (38) is being guided so as to slide along the slope portion (39) by the vertical slide of the shift member (31).

4. The yarn feeding device (1) according to Claim 2,
wherein the shift operation means (63) includes
an insertion hole (64) that is open at a lower end portion of the shift member (61), the insertion hole (64) allowing a vertically middle portion of the swing arm (62) to be inserted therethrough so as to exert a frontward and backward bending force on the swing arm (62) together with the yarn feeding arm (17), the swing arm (62) having an upper end attached to the yarn feeding arm (17), and
a support pin (65) disposed on a lower end portion of the yarn feeding arm (17) to reverse the frontward and backward bending force exerted on the swing arm (62), and
wherein the yarn feeding port (19) is shifted between the reference position and the front or back position as a result of the support pin (65) reversing the frontward and backward bending force exerted on the swing arm (62) in accordance with the vertical slide of the shift member (61).

5. The yarn feeding device (1) according to any one of Claims 1 to 4, wherein the yarn feeding port (14, 19, 93) includes a plaiting-yarn feeding port (14, 19, 93), through which a plaiting yarn is fed during plaiting, in addition to a main-yarn feeding port (13, 86, 92), through which a main yarn is fed during plaiting.

6. The yarn feeding (1) device according to Claim 5, further comprising:

a decentering mechanism (4, 10, 9) that rotates with respect to the swing arm (2, 62, 89) around a horizontal axis (42, 102) extending in front and back directions of the swing arm (2, 62, 89), the decentering mechanism (4, 10, 9) including a decentering member (41, 101, 903) that includes a decentered shaft portion (43, 103) that is decentered with respect to the horizontal axis (42, 102),

wherein the plaiting-yarn feeding port (14, 19, 93) is located above the main-yarn feeding port (13, 86, 92) and is capable of being vertically brought close to or spaced apart from the main-yarn feeding port (13, 86, 92) using the decentered shaft portion (43, 103).

Drawing