Technical Field
[0001] 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.
Background Art
[0002] 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.
[0003] 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".
[0004] 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.
[0005] 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.
[0006] 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.
Citation List
Patent Literature
Summary of Invention
Technical Problem
[0008] 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.
[0009] 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.
[0010] 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.
Solution to Problem
[0011]
<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.
Effect of the Invention
[0012] 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.
[0013] 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.
[0014] 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.
[0015] 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.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] With the flat knitting machine according to the above <8>, loads applied to the knitting
yarn can be reduced with a circular wire.
[0020] 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.
Brief Description of Drawings
[0021]
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.
Description of Embodiments
Embodiment 1
[0022] 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.
[0023] 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.
[0024] 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.
Needle plate
[0025] 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.
[0026] 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.
Fixed sinker
[0027] 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.
[0028] 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.
[0029] 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.
Movable sinker
[0030] 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.
[0031] 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.
[0032] 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.
[0033] 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.
[0034] 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.
[0035] 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.
[0036] 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.
[0037] 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.
[0038] 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.
[0039] 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.
[0040] 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.
[0041] 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.
Swing mechanism
[0042] 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.
[0043] 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.
[0044] 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.
[0045] 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.
[0046] 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.
[0047] 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.
[0048] 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.
[0049] 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.
Embodiment 2
[0050] 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.
[0051] 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.
[0052] 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.
[0053] 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.
Summary
[0054] 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.
List of Reference Numerals
[0055]
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
1. A flat knitting machine (1, 8)
characterized by comprising:
a needle bed (2) on which a plurality of needles (21) are disposed so as to be able
to advance and retreat;
a fixed sinker (3) immovably fixed to the needle bed (2) at a position near a needle
bed gap (11) and configured to form a sinker loop (91) of a knitted fabric (9) that
is held on the needle bed (2);
a movable sinker (4, 4α) disposed at a position next to the fixed sinker (3) on the
needle bed (2) and configured to swing so as to press the sinker loop (91) downward
of the needle bed gap (11),
the movable sinker (4, 4α) having:
a knitting yarn catching portion (4B) configured to catch the sinker loop (91) when
the sinker loop (91) is pressed down; and
a first protrusion (4A) disposed at a position further away from the needle bed gap
(11) than the knitting yarn catching portion (4B) and configured to be interposed
between the fixed sinker (3) and the sinker loop (91) when the sinker loop (91) is
pressed down;
a loop stopper (22) configured to, when a knitting yarn (90) is drawn in with a hook
(21F) of a needle (21), the needle (21) being one of the plurality of the needles
(21), to form a new loop (92) following a previous loop (93) in a wale direction,
temporarily stop the previous loop (93); and
a swing mechanism (5) configured to swing the movable sinker (4, 4α) between a retracted
position and a pressing position,
wherein the retracted position is a position where the knitting yarn catching portion
(4B) is positioned at a position farthest from the sinker loop (91),
the pressing position is a position where the knitting yarn catching portion (4B)
is positioned at a position where the knitting yarn catching portion (4B) presses
the sinker loop (91) downward of the needle bed gap (11),
a leading end portion (4a) of the first protrusion (4A) at the retracted position
is positioned at a position overlapping the knitting yarn (90) extending from the
hook (21F) to the fixed sinker (3) as viewed from a longitudinal direction of the
needle bed (2),
when swinging the movable sinker (4, 4α) from the retracted position to the pressing
position, the swing mechanism (5) swings the movable sinker (4, 4α) so that the leading
end portion (4a) moves along an outer shape of the loop stopper (22), and thereafter
swings the movable sinker (4, 4α) toward the pressing position, and
while the leading end portion (4a) moves along the outer shape, the first protrusion
(4A) 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).
2. The flat knitting machine (1) according to claim 1,
wherein the first protrusion (4A) at the retracted position overlaps the knitting
yarn (90) extending from the hook (21F) to the loop stopper (22) as viewed from the
longitudinal direction of the needle bed (2).
3. The flat knitting machine (1) according to claim 1 or 2,
wherein the movable sinker (4) includes a first working piece (41) including the knitting
yarn catching portion (4B) and the first protrusion (4A), and
the first working piece (41) of the movable sinker (4) at the retracted position is
positioned within an outer edge of the fixed sinker (3) as viewed from the longitudinal
direction.
4. The flat knitting machine (1) according to claim 3,
wherein the first working piece (41) includes a second protrusion (4C) disposed closer
to the needle bed gap (11) than the knitting yarn catching portion (4B),
the knitting yarn catching portion (4B) is disposed between the first protrusion (4A)
and the second protrusion (4C), and
the second protrusion (4C) of the movable sinker (4) at the retracted position is
positioned upward of the knitting yarn (90) relative to the needle bed in a direction
orthogonal to an advancing/retreating direction of the needle (21) as viewed from
the longitudinal direction, the knitting yarn (90) extending from the fixed sinker
(3) to the hook (21F).
5. The flat knitting machine (1) according to claim 3,
wherein the swing mechanism (5) includes a plurality of cam portions (4X, 4Y, 4P,
4Q) formed in the movable sinker (4), and a plurality of cam receiving portions (25,
26, 28, 29) engaging with the respective cam portions (4X, 4Y, 4P, 4Q), and
the plurality of cam receiving portions (25, 26, 28, 29) are immovably fixed to the
needle bed (2).
6. The flat knitting machine (1) according to claim 5,
wherein the movable sinker (4) includes a restricting portion (4D) formed at a position
closer to the loop stopper (22) than the plurality of cam receiving portions (25,
26), and
with the movable sinker (4) positioned at the retracted position, the restricting
portion (4D) engages with a temporary stopping member (23) immovably disposed on the
needle bed (2) and restrains the movable sinker (4) from moving upward of the needle
bed (2) in a direction orthogonal to the advancing/retreating direction of the needle
(21).
7. The flat knitting machine (1) according to claim 6,
wherein the movable sinker (4) includes a second working piece (44) formed below the
first working piece (41) and configured to act on the knitted fabric (9) to press
the knitted fabric (9) downward of the needle bed gap (11), and
the restricting portion (4D) is formed in the second working piece (44).
8. The flat knitting machine (1) according to claim 1 or 2,
wherein the loop stopper (22) is constituted by a wire having a circular cross section
passing through the fixed sinker (3).
9. A knitting method for a knitted fabric using a flat knitting machine (1, 8),
the flat knitting machine (1, 8) including:
a needle bed (2) on which a plurality of needles (21) are disposed so as to be able
to advance and retreat;
a fixed sinker (3) immovably fixed to the needle bed (2) at a position near a needle
bed gap (11) and configured to form a sinker loop (91) of a knitted fabric (9) that
is held on the needle bed (2);
a movable sinker (4, 4α) disposed at a position next to the fixed sinker (3) on the
needle bed (2) and configured to swing so as to press the sinker loop (91) downward
of the needle bed gap (11),
the movable sinker (4, 4α) having:
a knitting yarn catching portion (4B) configured to catch the sinker loop (91) when
the sinker loop (91) is pressed down; and
a first protrusion (4A) disposed at a position further away from the needle bed gap
(11) than the knitting yarn catching portion (4B) and configured to be interposed
between the fixed sinker (3) and the sinker loop (91) when the sinker loop (91) is
pressed down;
a swing mechanism (5) configured to swing the movable sinker (4, 4α) between a retracted
position and a pressing position; and
a loop stopper (22) configured to, when a knitting yarn (90) is drawn in with a hook
(21F) of a needle (21), the needle (21) being one of the plurality of needles (21),
to form a new loop (92) following a previous loop (93) in a wale direction, temporarily
stop the previous loop (93),
the method characterized in that
the swing mechanism (5) is configured to:
move the movable sinker (4) so that, in the retracted position, the knitting yarn
catching portion (4B) is positioned at a position farthest from the sinker loop (91),
and a leading end portion (4a) of the first protrusion (4A) is positioned at a position
overlapping the knitting yarn (90) extending from the hook (21F) to the fixed sinker
(3) as viewed from a longitudinal direction of the needle bed (2);
move the movable sinker (4, 4α) so that, in the pressing position, the knitting yarn
catching portion (4B) is positioned at a position where the knitting yarn catching
portion (4B) presses the sinker loop (91) downward of the needle bed gap (11); and
when advancing the needle (21) toward the needle bed gap (11) and swinging the movable
sinker (4, 4α) from the retracted position to the pressing position, swing the movable
sinker (4, 4α) so that the leading end portion (4a) moves along an outer shape of
the loop stopper (22), and thereafter swing the movable sinker (4, 4α) toward the
pressing position, and
while the leading end portion (4a) moves along the outer shape, the first protrusion
(4A) 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).