The present invention relates to a flat knitting machine including a movable sinker, and a knitting method for a knitted fabric using the movable sinker.

A flat knitting machine that automatically knits a knitted fabric has a pair of front and back needle beds facing each other with a needle bed gap therebetween. A plurality of needles are disposed next to each other on each needle bed. Patent Literatures 1 and 2 each disclose a flat knitting machine that includes a fixed sinker and a movable sinker in the vicinity of a needle bed gap between needle beds. The needle bed gap is a gap formed between the pair of front and back needle beds. In the following description, the terms "upper side/above/upward" and "lower side/below/downward" refer to the upper side and the lower side relative to the installation surface of the flat knitting machine. The phrases "above/upward of a needle bed" and "below/downward of a needle bed" refer to directions orthogonal to the direction in which the needle advances and retreats, as viewed from the needle bed.

FIG. 8 is a partial top view of a needle bed 2 of a flat knitting machine 100 that includes a fixed sinker 3 and a movable sinker 400. The depth direction with respect to the paper surface of FIG. 8 corresponds to the downward direction relative to a needle bed gap 11. A plurality of needle plates 20 are disposed next to each other at intervals on the needle bed 2. Needles 21 are disposed between adjacent needle plates 20. The movable sinker 400 and the fixed sinker 3 are disposed on the left side of each needle 21. The fixed sinker 3 is a member for forming a sinker loop 91, which connects stitches to each other, by holding down a knitting yarn so that the whole knitting yarn is not drawn into the needle bed 2 when the knitting yarn fed to a hook 21F of the needle 21 is drawn into the needle bed 2. The size of a stitch to be formed on the hook 21F is set by adjusting a drawing amount of the needle while the fixed sinker 3 forms the sinker loop 91. This setting of the stitch size will be referred to as "stitch density deciding".

The flat knitting machine 100 includes a loop stopper 22 (corresponding to a knitting yarn holding wire in Patent Literature 1) for temporarily stopping a previous loop 93, which is a stitch held at the needle 21, when knitting a new loop 92, which is a stitch that follows the previous loop 93 in the wale direction. When the needle 21 is drawn in to knit the new loop 92, the previous loop 93 is knocked over from the hook 21F due to the loop stopper 22 temporarily stopping the previous loop 93. Thus, the shape of the new loop 92 is stabilized. When a new stitch is knitted following the new loop 92 shown in the figure in the wale direction, the new loop 92 in the figure then becomes a previous loop.

The movable sinker 400 is a member that serves mainly to hold down the sinker loop 91 of the previous loop 93 when the needle 21 is advanced toward the needle bed gap 11 in order to knit the new loop 92 following the previous loop 93 in the wale direction. The movable sinker 400 is swung so as to press down the sinker loop 91 downward of the needle bed gap 11. The portion of the movable sinker 400 that presses down the sinker loop 91 is referred to as a knitting yarn receiving portion or a knitting yarn catching portion. In this specification, this portion is referred to as a knitting yarn catching portion 420. The knitting yarn catching portion 420 is formed on an end face of the movable sinker 400 that faces downward of the needle bed 2 as indicated by dotted lines.

In the flat knitting machine 100 that includes the fixed sinker 3 and the movable sinker 400, when the knitting yarn catching portion 420 of the movable sinker 400 comes into contact with a knitting yarn and presses it down, the knitting yarn may be clamped into the gap between the fixed sinker 3 and the movable sinker 400 that are next to each other. As a countermeasure against this issue, the movable sinker 400 in Patent Literatures 1 and 2 has a protrusion 410 disposed at a position farther from the needle bed gap 11 than the knitting yarn catching portion 420. The protrusion 410 is formed on an end face of the needle bed 2 of the movable sinker 400 that faces downward of the needle bed as indicated by dotted lines. Before the movable sinker 400 swings, the protrusion 410 is located upward of the sinker loop 91 relative to the needle bed (i.e., on the near side with respect to the paper surface of FIG. 8) , and is not in contact with the sinker loop 91. When the movable sinker 400 swings, the protrusion 410 is inserted between the sinker loop 91 and the fixed sinker 3, thereby preventing the knitting yarn from being clamped.

• Patent Literature 1: JP 2017-89033A
• Patent Literature 2: JP 2024-56553A

It may be difficult to insert the protrusion 410 between the sinker loop 91 and the fixed sinker 3, depending on knitting conditions for knitting the new loop 92. The sinker loop 91 extending from the fixed sinker 3 disposed at the left end in FIG. 8 extends to the opposing needle bed (not shown). In this state, for example, when the opposing needle bed is racked to the left, the sinker loop 91 is strongly pulled to the left side. In this case, the sinker loop 91 becomes difficult to bend, and the gap between the fixed sinker 3 and the sinker loop 91 becomes small. This may prevent the protrusion 410 from being inserted between the sinker loop 91 and the fixed sinker 3. In addition, when the needle 21 greatly retreats from the needle bed gap 11, the gap between the sinker loop 91 and the fixed sinker 3 becomes small, which may prevent the protrusion 410 from being inserted between the sinker loop 91 and the fixed sinker 3.

To solve the above issue, it is conceivable to elongate the protrusion 410 downward of the needle bed (i.e., toward the far side on the paper surface of FIG. 8) so that the protrusion 410 is always located between the sinker loop 91 and the fixed sinker 3. In this case, there is a concern that when the needle 21 is retreated to form the new loop 92, the protrusion 410 may come into contact with the sinker loop 91, making it impossible to accurately carry out stitch density deciding for the new loop 92.

An object of the present invention is to provide a flat knitting machine that can accurately carry out stitch density deciding and in which a sinker loop is unlikely to be clamped between a fixed sinker and a movable sinker. Another object of the present invention is to provide a knitting method for a knitted fabric by which stitch density deciding can be accurately carried out and a sinker loop is unlikely to be clamped between a fixed sinker and a movable sinker.

• <1> A flat knitting machine according to an aspect of the present invention includes: a needle bed on which a plurality of needles are disposed so as to be able to advance and retreat; a fixed sinker immovably fixed to the needle bed at a position near a needle bed gap and configured to form a sinker loop of a knitted fabric that is held on the needle bed; a movable sinker disposed at a position next to the fixed sinker on the needle bed and configured to swing so as to press the sinker loop downward of the needle bed gap, and a loop stopper configured to, when a knitting yarn is drawn in with a hook of a needle, the needle being one of the plurality of the needles, to form a new loop following a previous loop in a wale direction, temporarily stop the previous loop. The movable sinker includes: a knitting yarn catching portion configured to catch the sinker loop when the sinker loop is pressed down; and a first protrusion disposed at a position further away from the needle bed gap than the knitting yarn catching portion and configured to be interposed between the fixed sinker and the sinker loop when the sinker loop is pressed down. The flat knitting machine includes a swing mechanism configured to swing the movable sinker between a retracted position and a pressing position. The retracted position is a position where the knitting yarn catching portion is positioned at a position farthest from the sinker loop. The pressing position is a position where the knitting yarn catching portion is positioned at a position where the knitting yarn catching portion presses the sinker loop downward of the needle bed gap. A leading end portion of the first protrusion at the retracted position is positioned at a position overlapping the knitting yarn extending from the hook to the fixed sinker as viewed from a longitudinal direction of the needle bed. When swinging the movable sinker from the retracted position to the pressing position, the swing mechanism swings the movable sinker so that the leading end portion moves along an outer shape of the loop stopper, and thereafter swings the movable sinker toward the pressing position. While the leading end portion moves along the outer shape, the first protrusion overlaps the knitting yarn extending from the fixed sinker to the hook as viewed from the longitudinal direction of the needle bed.
• <2> In the flat knitting machine according to the above <1>, the first protrusion at the retracted position may overlap the knitting yarn extending from the hook to the loop stopper as viewed from the longitudinal direction of the needle bed.
• <3> In the flat knitting machine according to the above <1> or <2>, the movable sinker may include a first working piece including the knitting yarn catching portion and the first protrusion. In this case, the first working piece of the movable sinker at the retracted position may be located within an outer edge of the fixed sinker as viewed from the longitudinal direction.
• <4> In the flat knitting machine according to the above <3>, the first working piece may include a second protrusion disposed closer to the needle bed gap than the knitting yarn catching portion, and the knitting yarn catching portion may be disposed between the first protrusion and the second protrusion. In this case, the second protrusion of the movable sinker at the retracted position may be positioned upward of the knitting yarn relative to the needle bed in a direction orthogonal to an advancing/retreating direction of the needle as viewed from the longitudinal direction, the knitting yarn extending from the fixed sinker to the hook.
• <5> In the flat knitting machine according to the above <3> or <4>, the swing mechanism may include a plurality of cam portions formed in the movable sinker, and a plurality of cam receiving portions engaging with the respective cam portions. In this case, the plurality of cam receiving portions may be immovably fixed to the needle bed.
• <6> In the flat knitting machine according to the above <5>, the movable sinker may include a restricting portion formed at a position closer to the loop stopper than the plurality of cam receiving portions. In this case, with the movable sinker positioned at the retracted position, the restricting portion may engage with a temporary stopping member immovably disposed on the needle bed and restrain the movable sinker from moving upward of the needle bed in a direction orthogonal to the advancing/retreating direction of the needle.
• <7> In the flat knitting machine according to the above <6>, the movable sinker may include a second working piece formed below the first working piece and configured to act on the knitted fabric to press the knitted fabric downward of the needle bed gap. In this case, the restricting portion may be formed in the second working piece.
• <8> In the flat knitting machine according to any one of the above <1> to <7>, the loop stopper may be constituted by a wire having a circular cross section passing through the fixed sinker.
• <9> A knitting method for a knitted fabric according to an aspect of the present invention is a knitting method for a knitted fabric using a flat knitting machine. The flat knitting machine includes: a needle bed on which a plurality of needles are disposed so as to be able to advance and retreat; a fixed sinker immovably fixed to the needle bed at a position near a needle bed gap and configured to form a sinker loop of a knitted fabric that is held on the needle bed; a movable sinker disposed at a position next to the fixed sinker on the needle bed and configured to swing so as to press the sinker loop downward of the needle bed gap; a swing mechanism configured to swing the movable sinker between a retracted position and a pressing position; and a loop stopper configured to, when a knitting yarn is drawn in with a hook of a needle, the needle being one of the plurality of needles, to form a new loop following a previous loop in a wale direction, temporarily stop the previous loop. The movable sinker includes: a knitting yarn catching portion configured to catch the sinker loop when the sinker loop is pressed down; and a first protrusion disposed at a position further away from the needle bed gap than the knitting yarn catching portion and configured to be interposed between the fixed sinker and the sinker loop when the sinker loop is pressed down. The swing mechanism is configured to move the movable sinker so that, in the retracted position, the knitting yarn catching portion is positioned at a position farthest from the sinker loop, and a leading end portion of the first protrusion is positioned at a position overlapping the knitting yarn extending from the hook to the fixed sinker as viewed from a longitudinal direction of the needle bed. The swing mechanism is configured to move the movable sinker so that, in the pressing position, the knitting yarn catching portion is positioned at a position where the knitting yarn catching portion presses the sinker loop downward of the needle bed gap. Furthermore, when advancing the needle toward the needle bed gap and swinging the movable sinker from the retracted position to the pressing position, the swing mechanism is configured to swing the movable sinker so that the leading end portion moves along an outer shape of the loop stopper, and thereafter swing the movable sinker toward the pressing position. While the leading end portion moves along the outer shape, the first protrusion overlaps the knitting yarn extending from the fixed sinker to the hook as viewed from the longitudinal direction of the needle bed.

With the flat knitting machine according to the above <1>, when the movable sinker swings from the retracted position to the pressing position, the leading end portion of the first protrusion of the movable sinker swings to follow the outer shape of the loop stopper. Thus, the sinker loop is unlikely to be clamped between the movable sinker and the fixed sinker. Further, if the leading end portion of the first protrusion is positioned at a position overlapping the knitting yarn extending from the hook to the fixed sinker in the retreated position, the first protrusion is unlikely to interfere with the sinker loop. Therefore, the first protrusion of the movable sinker at the retracted position is unlikely to affect stitch density deciding for the new loop.

With the flat knitting machine according to the above <2>, the first protrusion is disposed particularly at a portion of the knitting yarn extending from the hook to the fixed sinker via the loop stopper, the portion extending from the hook to the loop stopper. The first protrusion disposed at this position is highly unlikely to interfere with the sinker loop during stitch density deciding for the new loop. Therefore, the first protrusion can be prevented from affecting stitch density deciding for the new loop.

With the flat knitting machine according to the above <3>, the first working piece can be prevented from interfering with a knitting yarn that is fed from above the needle bed gap and extends to a needle. Therefore, when the new loop is formed by the needle, the shape of the new loop is easily stabilized.

With the flat knitting machine according to the above <4>, the second protrusion of the movable sinker positioned at the retracted position does not interfere with the knitting yarn. This facilitates catching the sinker loop with the knitting yarn catching portion.

With the flat knitting machine according to the above <5>, the movable sinker can be displaced with a simple structure so that the leading end portion of the first protrusion follows the outer shape of the loop stopper.

According to the flat knitting machine according to the above <6>, it is possible to restrain the movable sinker from moving upward of the needle bed, and to prevent the first protrusion from slipping out from between the fixed sinker and the knitting yarn. Further, the position of the first working piece of the movable sinker can be determined accurately.

With the flat knitting machine according to the above <7>, the second working piece can press the knitted fabric downward of the needle bed gap. Further, providing the restricting portion on the second working piece disposed at a position near the loop stopper facilitates preventing the movable sinker from moving upward of the needle bed.

With the flat knitting machine according to the above <8>, loads applied to the knitting yarn can be reduced with a circular wire.

With the knitting method for a knitted fabric according to the above <9>, when the movable sinker swings from the retracted position to the pressing position, the leading end portion of the first protrusion of the movable sinker swings to follow the outer shape of the loop stopper. Thus, the knitting yarn is unlikely to be clamped between the movable sinker and the fixed sinker. Therefore, knitting of a knitted fabric is easily stabilized. Further, since the first protrusion draws such a swing path, the first protrusion of the movable sinker located at the retracted position is unlikely to affect stitch density deciding for the new loop. Thus, the size of the stitch is easily stabilized.

• FIG. 1 is a schematic configuration diagram of a needle bed of a flat knitting machine according to Embodiment 1, in the vicinity of a needle bed gap.
• FIG. 2 illustrates a state in which a movable sinker of the flat knitting machine shown in FIG. 1 is positioned at a retracted position.
• FIG. 3 illustrates the movable sinker of the flat knitting machine shown in FIG. 1 positioned at a pressing position.
• FIG. 4 illustrates a swing path of the movable sinker in the vicinity of a loop stopper.
• FIG. 5 is a schematic diagram of the movable sinker of the flat knitting machine according to Embodiment 1.
• FIG. 6 is a schematic diagram of a cam system mounted on a carriage of the flat knitting machine according to Embodiment 1.
• FIG. 7 is a schematic configuration diagram of a needle bed of a flat knitting machine according to Embodiment 2, in the vicinity of a needle bed gap.
• FIG. 8 is a schematic top view showing a needle bed of a conventional flat knitting machine, in the vicinity of a needle bed gap.

A flat knitting machine 1 according to an embodiment will be described with reference to FIGS. 1 to 6. The flat knitting machine 1 according to the embodiment may be a two-bed or four-bed flat knitting machine. FIG. 1 shows only one needle bed 2 of a two-bed flat knitting machine 1. In the actual flat knitting machine 1, needle beds having the same configuration as the needle bed 2 shown in the figure are disposed symmetrically with the needle bed gap 11 therebetween. Further, in FIG. 1, only a needle body with a hook 21F of a needle 21 provided on the needle bed 2 is shown. The needle 21 is a latch needle. The needle 21 may alternatively be a compound needle having a needle body with a hook and a slider.

The flat knitting machine 1 includes a carriage 10 that reciprocates on the needle bed 2. The reciprocating direction of the carriage 10 corresponds to the longitudinal direction of the needle bed 2, i.e., the direction toward the far side with respect to the paper surface of FIG. 1. A cam system (not shown) is mounted on the carriage 10. In response to the cam system acting on a butt (not shown) of the needle 21, the needle 21 advances toward or retreats from the needle bed gap 11. A knitted fabric 9 is knitted with advancing and retreating movements of the needle 21. The knitted fabric 9 knitted by the needle 21 hangs downward of the needle bed gap 11. Although the knitted fabric 9 is simplified in FIGS. 1 to 4, in practice, the knitted fabric 9 is formed by a plurality of loops continuously arranged in the wale direction.

As shown in FIG. 1, the needle bed 2 of the flat knitting machine 1 has a plurality of plate grooves 2G disposed next to each other at predetermined intervals in the longitudinal direction of the needle bed 2 (i.e., a direction toward the far side with respect to the paper surface). A needle plate 20 is fitted into each of the plate grooves 2G. A space between two adjacent needle plates 20 functions as a needle groove. The needle 21 is accommodated in the needle groove. A fixed sinker 3 and a movable sinker 4 are disposed next to each other at a leading end portion of the needle bed 2 on the needle bed gap 11 side. The needle 21, the movable sinker 4, and the fixed sinker 3 are arranged in this order from the near side to the far side with respect to the paper surface. A main difference between the configuration of the flat knitting machine 1 according to this embodiment and the conventional configuration lies in the configuration of the movable sinker 4. Among the components of the flat knitting machine 1, those that are closely related to the movable sinker 4 will be mainly described below.

The needle plate 20 is a plate-shaped member made of a metal material, for example. The movable sinker 4 (described later) and a lever 6 for swinging the movable sinker 4 are disposed on the near side of the needle plate 20 with respect to the paper surface. The needle plate 20 has a recess 20C into which an elastic leg piece 43 of the movable sinker 4 (described later) is fitted. The elastic force of the elastic leg piece 43 biases a portion of the movable sinker 4 on the needle bed gap 11 side downward of the needle bed gap 11.

A support plate 24 that supports the movable sinker 4 (described later) from far side with respect to the paper surface is attached to the needle plate 20. A left portion of the support plate 24, i.e., a portion far from the needle bed gap 11 is attached to a surface of the needle plate 20 on the side opposite to a surface facing the lever 6. A right portion of the support plate 24, i.e., a portion close to the needle bed gap 11 protrudes from the needle plate 20 toward the needle bed gap 11. This protruding portion overlaps the movable sinker 4 as viewed from the longitudinal direction of the needle bed 2, and is in surface contact with the movable sinker 4 to support the movable sinker 4. The position of the first working piece 41 of the movable sinker 4 (described later) can be adjusted by adjusting the position of the support plate 24 relative to the needle plate 20. Wires extending in the longitudinal direction of the needle bed 2 pass through the support plate 24. As shown in FIG. 2, these wires function as cam receiving portions 25 and 26 that engage with respective cam portions 4X and 4Y of the movable sinker 4. The cam receiving portions 25 and 26 need not necessarily be wires, and may be, for example, bosses projecting from the support plate 24 toward the near side with respect to the paper surface. The support plate 24 may be integrated with the needle plate 20.

The fixed sinker 3 is a plate-shaped member made of a metal material, for example. The fixed sinker 3 includes a bent, long and narrow arm portion 30 and a flat plate-shaped stitch density deciding portion 31 formed at a leading end of the arm portion 30. One end (an end on the side opposite to the stitch density deciding portion 31) of the arm portion 30 is fixed to a lower portion of the needle bed 2. The fixed sinker 3 is immovable relative to the needle bed 2. Meanwhile, the stitch density deciding portion 31 protrudes toward the needle bed gap 11. The stitch density deciding portion 31 has a hole on the needle bed gap 11 side, and a loop stopper 22 (see also FIG. 4) extending in the longitudinal direction of the needle bed 2 is inserted into this hole.

The fixed sinker 3 and the loop stopper 22 have the same functions as those described in Patent Literature 1. That is to say, as shown in FIG. 2, the fixed sinker 3 is a member that presses down a knitting yarn 90 with the stitch density deciding portion 31 when the knitting yarn 90 is drawn into the needle bed 2 side (i.e., away from the needle bed gap 11) by the hook 21F of the needle 21 such that the whole knitting yarn 90 is not drawn to the needle bed 2 side, and forms a sinker loop 91 of the knitted fabric 9. Meanwhile, when the knitting yarn 90 is drawn by the hook 21F of the needle 21 to knit a new loop 92, the loop stopper 22 temporarily stops a previous loop 93 held at the hook 21F, as shown in FIG. 4. As a result of the loop stopper 22 temporarily stopping the previous loop 93, the previous loop 93 is knocked over from the new loop 92.

The loop stopper 22 in this example is formed of a wire having a circular cross section. With the loop stopper 22 having a circular cross section, a load is unlikely to be applied to the knitting yarn 90 in contact with the loop stopper 22. The cross section of the wire constituting the loop stopper 22 may have a shape other than a circle, for example, a polygon such as a rectangle. Unlike this example, the loop stopper may be formed by a leading end of the needle bed 2 on the needle bed gap 11 side, as in the flat knitting machine disclosed in Japanese Patent No. 4408803.

The movable sinker 4 is a plate-shaped member made of a metal material, for example. As shown in FIG. 5, the movable sinker 4 has a bent arm shape. The movable sinker 4 has the first working piece 41 and the second working piece 44 in a part disposed on the needle bed gap 11 side (see FIG. 2 and other figures). The second working piece 44 is not essential.

The first working piece 41 is a portion that acts on the sinker loop 91, and includes a first protrusion 4A, a knitting yarn catching portion 4B, and a second protrusion 4C. The first protrusion 4A and the second protrusion 4C extend downward of the needle bed gap 11 when the first and second protrusions 4A and 4C are attached to the needle bed 2 as shown in FIGS. 2 and 4. The first protrusion 4A is an essential component, while the second protrusion 4C is not an essential component. The knitting yarn catching portion 4B is a portion for catching the sinker loop 91, and is a recess formed between the first protrusion 4A and the second protrusion 4C in this example. As shown in FIGS. 2 and 4, the knitting yarn catching portion 4B is recessed upward of the needle bed 2 when the knitting yarn catching portion 4B is attached to the needle bed 2. As will be described later, the knitting yarn catching portion 4B is a portion at which the sinker loop 91 is positioned when the movable sinker 4 pressed down the sinker loop 91. When the sinker loop 91 is pressed down, the second protrusion 4C makes it difficult for the sinker loop 91 to move upward of the needle bed gap 11 to detach from the knitting yarn catching portion 4B.

The second working piece 44 is formed below the first working piece 41. The second working piece 44 functions to act on the knitted fabric 9 to press the knitted fabric 9 downward of the needle bed gap 11. The second working piece 44 has a substantially triangular shape, and its corner near the needle bed gap 11 acts on the knitted fabric 9. A portion between the second working piece 44 and the first working piece 41 is recessed upward of the needle bed.

The second working piece 44 in this example includes a restricting portion 4D extending in a direction away from the needle bed gap 11. More specifically, the restricting portion 4D is formed at the position of a corner of the substantially triangular second working piece 44, the position being distant from the needle bed gap 11. The restricting portion 4D functions to restrict movement of the movable sinker 4 upward of the needle bed, as will be described later.

As shown in FIGS. 1 to 3, a rear end portion 42 of the movable sinker 4 protrudes in a direction away from the needle bed gap 11. A lever 6 of a swing mechanism 5 (described later) engages with the rear end portion 42. The elastic leg piece 43 is formed in the vicinity of the rear end portion 42 of the movable sinker 4. The elastic leg piece 43 in this example is provided in the rear end portion 42 on a needle groove bottom side. The elastic leg piece 43 extends toward the needle bed gap 11, is then folded back in a U-shape, and extends in a direction away from the needle bed gap 11. An end portion 43E of the elastic leg piece 43 is formed in a droplet shape, as shown in FIG. 5. The end portion 43E is fitted into the recess 20C of the needle plate 20, as shown in FIGS. 1 to 3. The elastic force of the elastic leg piece 43 biases the first working piece 41 of the movable sinker 4 downward of the needle bed gap 11.

The movable sinker 4 in this example includes a plurality of cam portions 4X and 4Y that are independent of each other. The cam portions 4X and 4Y in this example are cam grooves. The cam portion 4X in this example, which is a cam groove, is an elongated hole that is bent to protrude in a direction away from the needle bed gap 11, and the cam portion 4Y is an elongated hole that is bent to protrude in a direction approaching the needle bed 2. As shown in FIG. 2, the cam receiving portions 25 and 26 extending from the support plate 24 toward the movable sinker 4 are fitted into the respective cam portions 4X and 4Y. The swing path of the movable sinker 4 is determined in accordance with the shapes of the cam portions 4X and 4Y. In other words, the shapes of the cam portions 4X and 4Y may be determined in accordance with a desired swing path of the movable sinker 4. Unlike this example, the cam portions 4X and 4Y may be recesses that are recessed in the thickness direction of the movable sinker 4. The number of cam portions 4X and 4Y in this example is two, but may alternatively be one or three or more.

The movable sinker 4 is swingable between a retracted position shown in FIG. 2 and a pressing position shown in FIG. 3. In the retracted position shown in FIG. 2, the knitting yarn catching portion 4B of the movable sinker 4 is positioned at a position farthest from the sinker loop 91. In the pressing position shown in FIG. 3, the knitting yarn catching portion 4B of the movable sinker 4 is positioned at a position where the knitting yarn catching portion 4B presses the sinker loop 91 downward of the needle bed gap 11. The movable sinker 4 presses down the sinker loop 91 when, for example, the needle 21 advances toward the needle bed gap 11 to knit a new loop 92.

The swing path of the movable sinker 4 in this example shown in FIG. 4 differs from an arc-shaped path of a movable sinker having a conventional structure. The movable sinker 4 positioned at the retracted position is indicated by a solid line in FIG. 4. A leading end portion 4a of the first protrusion 4A provided in the first working piece 41 of the movable sinker 4 overlaps the knitting yarn 90 extending from the fixed sinker 3 to the hook 21F as viewed from the longitudinal direction of the needle bed 2. More specifically, the leading end portion 4a in this example overlaps the knitting yarn 90 extending from the loop stopper 22 to the hook 21F as viewed from the longitudinal direction of the needle bed 2. At this position, even if the needle 21 is greatly retreated, the first protrusion 4A is unlikely to come into contact with the sinker loop 91, and is unlikely to affect stitch density deciding for the new loop 92. Here, the leading end portion 4a is a portion having a predetermined size including the leading end of the first protrusion 4A. The leading end portion 4a in this example is a portion having a rounded shape.

In this example, when the movable sinker 4 moves from the retracted position to the pressing position, first, the leading end portion 4a of the first protrusion 4A moves along the outer shape of the loop stopper 22 as indicated by phantom lines. More specifically, the leading end portion 4a moves along a predetermined surface 22S facing obliquely upward in an outer peripheral surface of the loop stopper 22. The predetermined surface 22S includes a portion of the outer peripheral surface that extends from a position above the needle bed to a forward position. Here, the term "forward" means the advancing direction of the needle 21. While the leading end portion 4a moves along the outer shape of the loop stopper 22, the first protrusion 4A is interposed between the sinker loop 91 and the fixed sinker 3. Therefore, the sinker loop 91 is effectively prevented from being clamped into the gap between the fixed sinker 3 and the movable sinker 4. The clearance between the leading end portion 4a of the first protrusion 4A and the predetermined surface 22S when the leading end portion 4a moves along the predetermined surface 22S is, for example, not more than the thickness of the knitting yarn 90. Such a clearance prevents the sinker loop 91 from turning around to the back side (i.e., the fixed sinker 3 side) of the first protrusion 4A. Although the clearance may be zero, the presence of the clearance prevents the occurrence of sliding resistance between the movable sinker 4 and the loop stopper 22, thereby stabilizing the operation of the movable sinker 4.

After the leading end portion 4a has moved along the outer shape of the loop stopper 22, the movable sinker 4 swings to the pressing position. This swing causes the knitting yarn catching portion 4B to catch the sinker loop 91 and press the sinker loop 91 downward of the needle bed gap 11.

When the movable sinker 4 is at the retracted position, the first working piece 41 of the movable sinker 4 as viewed from the longitudinal direction of the needle bed 2 is positioned within the outer edge of the fixed sinker 3. When the needle 21 is drawn into the needle bed to form the new loop 92, the movable sinker 4 is positioned at the retracted position. Accordingly, the first working piece 41 of the movable sinker 4 positioned at the retracted position does protrude outward of the outer edge of the fixed sinker 3. Thus, the first working piece 41 can be prevented from interfering with the knitting yarn fed from above the needle bed gap 11 and extending to the needle 21. That is to say, since the first working piece 41 does not hinder the formation of the new loop 92, the shape of the new loop 92 is stabilized when the new loop 92 is formed by the needle 21.

When the movable sinker 4 is at the retracted position, the restricting portion 4D of the second working piece 44 engages with a temporary stopping member 23, which is immovably disposed on the needle bed 2. The temporary stopping member 23 in this example is constituted by a wire extending through the fixed sinker 3 in the longitudinal direction of the needle bed 2. An engagement area between the restricting portion 4D and the temporary stopping member 23 is closer to the loop stopper 22 than the cam receiving portions 25 and 26. This enables the first working piece 41 of the movable sinker 4 to be accurately determined. Further, in this example, the restricting portion 4D engages with the temporary stopping member 23 for a certain period after the movable sinker 4 moved from the retracted position. Thus, the behavior of the movable sinker 4 is stable, and the first working piece 41 can be accurately determined in the vicinity of the needle bed gap 11. Further, the restricting portion 4D prevents the first working piece 41 from moving upward of the needle bed while the leading end portion 4a of the first protrusions 4A moves along the outer shape of the loop stopper 22.

The above-described movable sinker 4 in this example is swung by the swing mechanism 5 shown in FIG. 1. That is, the swing mechanism 5 swings the movable sinker 4 between the retracted position and the pressing position. The swing mechanism 5 in this example includes the lever 6 and an operating cam 50 for operating the lever 6. Here, the swing mechanism 5 also includes the cam portions 4X and 4Y and the cam receiving portions 25 and 26 for determining the swing path of the movable sinker 4.

The lever 6 has a rotary portion 60, a front arm 61 extending from the rotary portion 60 toward the needle bed gap 11, and a rear arm 62 extending from the rotary portion 60 toward the side opposite to the front arm 61. The rotary portion 60 has a slit. The slit is fitted onto a shaft 27 extending in the longitudinal direction of the needle bed 2. The shaft 27 in this example is a wire having a circular cross section. Thus, the lever 6 is rotatably supported about the shaft 27 by the needle bed 2.

The front arm 61 extends to the rear end portion 42 of the movable sinker 4. As shown in FIG. 1, the lever 6 rotates clockwise as a result of the operating cam 50, which is attached to the carriage 10, pressing the rear arm 62 upward of the needle bed. The front arm 61 presses the rear end portion 42 of the movable sinker 4 downward of the needle bed. As a result, as shown in FIG. 2, the first working piece 41 is lifted upward of the needle bed, and the movable sinker 4 is positioned at the retracted position.

The movable sinker 4 is biased toward the pressing position by the elastic force of the elastic leg piece 43. Thus, when the operating cam 50 ceases pushing up the rear arm 62, the rear end portion 42 lifts the front arm 61 upward of the needle bed, and the lever 6 rotates counterclockwise. As a result, the first working piece 41 of the movable sinker 4 is positioned at the pressing position as shown in FIG. 3.

Here, the lever 6 is not essential for the swing mechanism 5. In this case, the operating cam 50 may be configured to act directly on the movable sinker 4.

A description is now given of the shape of the operating cam 50 mounted on the carriage 10 and the timing of the operation of the movable sinker 4, with reference to FIG. 6. A knitting cam 15, a transferring cam 16, and the operating cam 50 that are mounted on the carriage 10 are shown in a lower diagram of FIG. 6. The knitting cam 15 is mainly used when forming a stitch with the needle 21. The transferring cam 16 is used when moving a stitch held on the needle 21 to another needle opposing the needle 21. In the lower diagram, the direction toward the near side with respect to the paper surface corresponds to the direction toward the needle bed 2. An upper diagram of FIG. 6 shows the uneven shape of the operating cam 50 as viewed from the needle bed gap 11 side. In the upper diagram, the direction toward the lower side with respect to the paper surface corresponds to the direction toward the needle bed 2. The configuration on the needle bed 2 is in the state shown in FIG. 2 at the timing indicated by a thick vertical broken line(II) in FIG. 6. The configuration on the needle bed 2 is in the state shown in FIG. 3 at the timing indicated by a thick vertical broken line (III) in FIG. 6.

A two-dot chain line shown at the position of the knitting cam 15 indicates a path of a butt of the needle 21 when the carriage 10 moves to the left during knitting with the needle 21. The butt is positioned at a position omitted in FIG. 1, i.e., a position further away from the needle bed gap 11 than the operating cam 50. The needle 21 is pushed up toward the needle bed gap 11 by the knitting cam 15 and then pulled down in a direction away from the needle bed gap 11.

A two-dot chain line shown at the position of the operating cam 50 indicates a path of the rear arm 62 that is pressed by the operating cam 50 when the carriage 10 moves to the left. The operating cam 50 in this example includes a movable portion 50M that is slidable in the left-right direction, i.e., in the moving direction of the carriage 10. Vertical two-dot chain lines extending from the upper diagram to the lower diagram indicate the sliding area of the movable portion 50M. In the example shown in FIG. 6, the movable portion 50M slides to the right. Accordingly, the rear arm 62 is not pressed by the movable portion 50M when the needle 21 advances toward the needle bed gap 11 during knitting, for example, and the rear arm 62 is pressed by the movable portion 50M when the needle 21 retreats from the needle bed gap 11. As already described, the movable sinker 4 is located at the pressing position, as shown in FIG. 3 while the rear arm 62 is not pressed by the operating cam 50. Accordingly, the movable sinker 4 is positioned at the pressing position when the needle 21 advances to the needle bed gap 11, and the movable sinker 4 is positioned at the retracted position when the needle 21 retreats. Here, when moving the carriage 10 to the right, the movable portion 50M need only be slid to the left.

In Embodiment 2, a flat knitting machine 8 that adjusts the swing path of a movable sinker with a configuration different from that in Embodiment 1 will be described with reference to FIG. 7. Needles are omitted in FIG. 7.

A movable sinker 4α according to Embodiment 2 includes an arc-shaped portion 48. A U-shaped recess 47, which is recessed downward of the needle bed 2α, is formed at a position above the needle bed 2α on the arc-shaped portion 48. Also, a recess 46, which is recessed in a U-shape toward the needle bed gap 11, is formed at a position closer to the needle bed gap 11 than the arc-shaped portion 48 on the movable sinker 4α. The recess 46 is smaller than the recess 47. The arc-shaped portion 48 of the movable sinker 4α is fitted into a semicircular recess 20E of a needle plate 20α. The radius of the recess 20E is slightly greater than the radius of the arc-shaped portion 48. The arc-shaped portion 48 can not only rotate within the recess 20E but also slightly change its position in the advancing/retreating directions of the needle.

The movable sinker 4α is biased toward the pressing position by the elastic force of a wire spring 49. The wire spring 49 has such a shape that a large J-shaped portion and a small J-shaped portion are continuously connected. The large J-shaped bent portion fits into the recess 47, and the small J-shaped bent portion fits into the recess 46. An end of the large J-shaped portion is stopped at a step 20D formed in the needle plate 20α. In FIG. 7, the movable sinker 4α positioned at the retracted position is indicated by a solid line.

An operating cam 70 of a swing mechanism 7 that swings the movable sinker 4α in this example projects from a carriage (not shown) toward the needle bed 2α. The movable sinker 4α is maintained in the retracted position due to the operating cam 70 pressing the rear end portion 42 of the movable sinker 4α. When the operating cam 70 ceases acting on the rear end portion 42, the movable sinker 4α swings toward the pressing position, as indicated by phantom lines. The shape of the first working piece 41 in this example is the same as that in Embodiment 1, but the shape of the second working piece 44 differs from that in Embodiment 1. In this example, the cam receiving portions 28 and 29 are disposed so as to sandwich the second working piece 44 that has a shape different from that in Embodiment 1. The cam receiving portions 28 and 29 in this example are constituted by wires extending in the longitudinal direction of the needle bed 2α. The cam receiving portions 28 and 29 pass through a plurality of fixed sinkers 3α disposed in the longitudinal direction of the needle bed 2α. Thus, the cam receiving portions 28 and 29 are immovably fixed to the needle bed 2α via the fixed sinkers 3α. The cam receiving portions 28 and 29 may be protrusions projecting from the fixed sinkers 3α. In response to the cam receiving portions 28 and 29 guiding the second working piece 44, the leading end portion 4a of the first working piece 41 of the movable sinker 4α swings along the outer shape of the loop stopper 22. In such a configuration, a portion of the outer peripheral edge of the second working piece 44 that engages with the cam receiving portion 28 functions as a cam portion 4P, and a portion of the outer peripheral edge of the second working piece 44 that engages with the cam receiving portion 29 functions as a cam portion 4Q. The cam portion 4P and the cam portion 4Q are constituted by different portions of the second working piece 44.

In Embodiments 1 and 2, a knitting method for a knitted fabric is implemented in which when the needle 21 is advanced toward the needle bed gap 11 and the movable sinker 4 (4α) is swung from the retracted position to the pressing position, the leading end portion 4a of the first protrusion 4A is moved along the outer shape of the loop stopper 22. The flat knitting machine 1 may have any configuration as long as the movable sinker 4 (4α) can be swung in this manner. According to the knitting method for a knitted fabric with such swing of the movable sinker 4 (4α), the knitting yarn 90 is unlikely to be clamped between the fixed sinker 3 (3α) and the movable sinker 4 (4α) during knitting of the knitted fabric 9, and the shape of the stitch is stabilized. Furthermore, stitch density deciding for the new loop 92 can be carried out accurately. As a result, the quality of the knitted fabric 9 is improved.

• 1, 8, 100 Flat knitting machine
• 10 Carriage; 11 Needle bed gap; 15 Knitting cam; 16 Transferring cam

• 2, 2α Needle bed; 2G Plate groove
  • 20, 20α Needle plate; 20C, 20E Recess; 20D Step
  • 21 Needle; 21F Hook
  • 22 Loop stopper: 22S Predetermined surface
  • 23 Temporary stop member; 24 Support plate
  • 25, 26, 28, 29 Cam receiving portion; 27 Shaft
• 3,3α Fixed sinker
  30 Arm portion; 31 Stitch density deciding portion
• 4,4α, 400 Movable sinker
  • 4a Leading end portion; 4A First protrusion; 4B Knitting yarn catching portion
  • 4C Second protrusion; 4D Restricting portion; 4P, 4Q, 4X, 4Y Cam portion
  • 41 First working piece; 42 Rear end portion; 43 Elastic leg piece; 43E End portion
  • 44 Second working piece; 46, 47 recess; 48 Arc-shaped portion; 49 Wire spring
  • 410 Protrusion; 420 Knitting yarn catching portion
• 5, 7 Swing mechanism; 50, 70 Operating cam; 50M Movable portion
• 6 Lever; 60 Rotary portion; 61 Front arm ; 62 Rear arm
• 9 Knitted fabric; 90 Knitting yarn; 91 Sinker loop; 92 New loop; 93 Previous loop