Technical Field of the Invention
[0001] The present invention relates to an apparatus for stabilizing weft insertion in a
water jet loom.
Background
[0002] In a water jet loom using pressured water as a fluid for weft insertion, there occurs
such a phenomenon as the injection water for weft insertion moves upward as it is
directed toward a weft arrival side opposite to a weft supply side. It is presumed
that this phenomenon occurs when a reed with a multiple reed dents arranged in parallel
between upper and lower caps performs oscillating motion, causing an updraft within
a weft inserting space ahead of the reed.
[0003] The updraft is considered to be caused, because, when the reed moves backward after
beating, the air on the side of a cloth fell is drawn toward the reed side by the
reed, and subsequently, when the reed moves forward, the drawn air is pushed back
toward the cloth fell side by the reed and goes upward.
[0004] Such a phenomenon of uprising of injection water is liable to happen at the time
of high-speed operation, water-saving operation and the like. When such obliquely
uprising injection water is caused, the uprising injection water damages the warp
or makes weft insertion unstable.
[0006] The conventional weft insertion stabilizer comprises an air flow constraining member
projecting toward a cloth fell side outside a range of a warp shedding and extending
in the weft inserting direction in a cap on the upside or downside of the reed or
at a location on the upside or downside of a reed holding member for holding the reed
on a sley. Thereby, the updraft of the air in a space for weft insertion within the
warp shedding is constrained by the air flow constraining member, so that the updraft
phenomenon of the injection water is constrained.
[0007] In the conventional weft insertion stabilizer, however, during the weft insertion
in a swinging process of the reed, an actual weft flying line is moved in the moving
direction of the warp, making the weft insertion unstable, thereby resulting in insertion
failure.
[0008] Such a change of the actual weft flying line is considered to be caused because,
when the reed moves backward (when the angle of the main shaft moves from 0°to 180°),
the weft inserting space is applied negative pressure and the actual weft flying line
moves toward the reed side, and when the reed moves forward (when the angle of the
main shaft moves from 180° to 0°), the weft inserting space is applied positive pressure
and the actual weft flying line moves toward the cloth fell side.
Summary
[0009] An object of the present invention is to stabilize an actual weft flying line by
constraining a change of atmospheric pressure of a weft inserting space.
[0010] The weft insertion stabilizer of a water jet loom according to the present invention
has a member projecting toward a cloth fell side outside a range of a warp shedding
on at least one of the upside and the downside of the reed and extending in the weft
inserting direction.
[0011] One weft insertion stabilizer according to the present invention forms a gap between
the member provided on at least one of the upside and the downside of the reed and
the reed or the reed holding member for holding the reed on the sley.
[0012] Another weft insertion stabilizer according to the present invention has a hole at
a location on the side of the reed in the member provided on at least one of the upside
and the downside of the reed.
[0013] The other weft insertion stabilizer according to the present invention forms a cutout
portion on the cloth fell side of the member provided on at least one of the upside
and the downside of the reed.
[0014] In the weft insertion stabilizer, by forming at least one of the gap, the hole and
the cutout portion, change of the atmospheric pressure of the weft inserting space
at its location can be constrained and the actual weft flying line can be prevented
from moving in the warp moving direction. Details are mentioned below.
[0015] With the backward movement of the reed, the air outside the weft inserting space
is taken into the weft inserting space through the gap, the hole or the cutout portion,
thereby constraining the weft inserting space from being applied negative pressure,
and at the time of forward movement of the reed, the air in the weft inserting space
is let out of the weft inserting space to the outside through the gap, the hole or
the cutout portion, thereby constraining the weft inserting space from being applied
positive pressure.
[0016] Since the atmospheric pressure change within the weft inserting space is constrained
accordingly, generation of the updraft at the original beating time is constrained
and, at the same time, change of the atmospheric pressure in the warp moving direction
is constrained. As a result, the actual weft flying line is much stabilized, thereby
decreasing the number of stopping times of the loom.
[0017] The weft insertion stabilizer can be further provided with a vent opened toward the
rear side of the reed and communicated to the upside gap or hole. Thereby, since the
vent is opened toward the rear side of the reed, the air outside the warp shedding
is positively and efficiently taken into the weft inserting space when the reed moves
backward, thereby more stabilizing the actual weft flying line.
[0018] The length dimension in the warp moving direction of the member provide on at least
one of the upside and the downside of the reed may differ by location in the weft
inserting direction, or the size of the gap or the hole of the member provided on
at least one of the upside and the downside of the reed in the warp moving direction
may differ by location in the weft inserting direction.
[0019] In place thereof, the position of the front edge of the member provided on at least
one of the upside and the downside of the reed and the position in the warp moving
direction of the front edge on the cloth fell side may differ by location in the weft
inserting direction.
[0020] In either case, the member provided on at least one of the upside and the downside
of the reed can include a plurality of pieces arranged side by side in the weft inserting
direction.
[0021] The position in the warp moving direction of the front edge of the member provided
on at least of the upside and downside of the reed on the cloth side is made to differ
by location in the weft inserting direction. The nearer the position is to the reed
side, the larger the cutout portion at the location becomes. The larger the cutout
portion, the more the passing amount of the air flow becomes. Thus, the updraft restraining
effect of the constraining member is reduced, so that the updraft is generated only
a little.
[0022] In actual weft insertion, as the weft flies toward the weft arrival side, the flying
force lowers, and the weft tends to fly downward by gravity. However, if the conditions
such as the length of the member or the size of the cutout portion, the gap or the
hole are set as above, the updraft is slightly generated by changing the conditions
according to the passing range of the weft when the reed moves forward, thereby constraining
the weft from flying downward and further stabilizing the actual weft flying line.
[0023] The foregoing conditions can be changed, for instance, by shortening the length in
the warp moving direction of the member, and enlarging the cutout portion by making
the position in the warp moving direction of the front edge of the member closer to
the reed side, or making the gap or the hole small, whereby the updraft within the
weft inserting space can be increased toward the weft arrival side.
Brief Description of the Drawings
[0024] Fig. 1 is a schematic view showing one example of a water jet loom provided with
the first embodiment of the weft insertion stabilizer according to the present invention.
[0025] Fig. 2 is a plan view seeing the weft insertion stabilizer shown in Fig. 1 from above
the reed
[0026] Fig. 3 is a view illustrating details and action of the weft insertion stabilizer
shown in Fig. 1.
[0027] Fig. 4 is a view illustrating details and action of the second embodiment of the
weft insertion stabilizer according to the present invention.
[0028] Fig. 5 is a view illustrating details and action of the third embodiment of the weft
insertion stabilizer according to the present invention.
[0029] Fig. 6 is a view illustrating details and action of the fourth embodiment of the
weft insertion stabilizer according to the present invention.
[0030] Fig. 7 is a plan view similar to Fig. 2 showing the fifth embodiment of the weft
insertion stabilizer according to the present invention.
[0031] Fig. 8 is a plan view similar to Fig. 2 showing the sixth embodiment of the weft
insertion stabilizer according to the present invention.
Detailed Description of Embodiments
Embodiment of Water Jet Loom
[0032] Referring to Figs. 1 through 3, the water jet loom 10 has a plurality of warp yarns
12 to be reeled out of a warp beam (not shown) in a sheet-like state passed through
a plurality of healds 16 supported in parallel at a plurality of heald frames 14 in
one-to-one correspondence, and by vertically moving the heald frames 14, the warp
yarns 12 are vertically moved to form a warp shedding 18.
[0033] The weft yarns (not shown) are injected together with the pressure water from a weft
insertion nozzle 22 while a reed 20 is positioned more upstream (on the side of the
heald frame 14) in the moving direction (i.e., forward and backward direction) of
the warp yarns 12 than the weft insertion nozzle 22 and inserted into a weft inserting
space 24 within the warp shedding 18 (see Fig. 3).
[0034] The inserted weft yarns are beaten against a cloth fell 26 by the reed 20 and woven
into a cloth 28. The cloth 28 is taken up by a cloth beam (not shown) through a plurality
of guide rolls 30.
[0035] A plurality of reed dents 32 of the reed 20 are supported on an upper and a lower
caps (i.e., cap portions) 34, 36 in parallel and the reed 20 is attached to the upper
end of a sley 42 by a plurality of reed holding members 38 and a plurality of screw
members 40 on the lower cap 36 so as not to move relatively.
[0036] The sley 42 is attached at its lower portion to a swinging shaft 44 extending in
the weft inserting direction so as not to relatively move. The swinging shaft 44 swings
about an axis extending in the weft inserting direction to synchronize with rotation
of the main shaft of the loom 10, namely, to reciprocate within a predetermined range
of angle. By this, the reed 20 is swung about the axis of the swinging shaft 44 and
performs reed beating.
[0037] Injection water from the weft insertion nozzle 22 is prevented from splashing forward
(i.e., downstream in the moving direction of the warp 12) and upward by a front shield
plate (i.e., a fixed cover) 46 and a splash guard (i.e., a movable cover) 48, respectively.
[0038] The front shield plate 46 extends over one guide roll 30 in the weft inserting direction
(i.e., in the direction of the weaving width and lateral direction), and attached
immovably at its right and left ends to a right and a left loom frames (not shown).
[0039] The splash guard 48 extends in the weft inserting direction in such a manner as to
cover a space above the warp 12 and the cloth 28 from the warp shedding 18 to one
guide roll 30 releaseably.
[0040] The splash guard 48 is rotatably supported on a support shaft 50 extending over the
weft 12 in the weft inserting direction, making the downstream end portion in the
moving direction of the warp 12 (i.e., the warp moving direction) abut the front shield
plate 46. Therefore, the splash guard 48 can open and close the upper space in the
front and rear areas of the cloth fell 26 by angularly rotating the splash guard 48
about the axis of the support shaft 50.
Embodiment 1 of Weft Insertion Stabilizer
[0041] The weft insertion stabilizer comprises a pair of air flow constraining members 52
and 54 respectively attached to the upper cap 34 and, on the lower side, to the cloth
fell side reed holding member 38.
[0042] Both air flow constraining members 52 and 54 are made of plate members and continuously
extend over the outside of the warp shedding 18 in the whole weft inserting direction
in a state of projecting from the upper cap 34 and the reed holding member 38 on the
cloth fell 26 side, respectively.
[0043] The upper air flow constraining member 52 has a Z-shaped vertical section and is
attached to the cloth fell 26 side of the upper cap 34 with a plurality of screw members
56.
[0044] The lower air flow constraining member 54 has an L-shaped vertical section and is
attached to the cloth fell 26 side of the lower reed holding member 38 with a plurality
of screw members 58.
[0045] A plurality of spacers 60 supported by the screw members 56 are arranged between
the air flow constraining members 52 and the cap 34. Therefore, the weft insertion
stabilizer comprises a plurality of gaps 62 extending in the weft inserting direction
near the reed 20 and between a mounting face which is formed with an end portion of
the air flow constraining member 52 turned back and a mounting face of the cap 34.
[0046] Those gaps 62 are spaces for communicating the upper and lower spaces of the air
flow constraining member 52 and permit the air in the upper and lower spaces of the
air flow constraining member 52 to pass. A plurality of gaps 62 adjoining in the weft
inserting direction are partitioned from each other by the spacers 60 (see Fig. 2).
In the illustration, the width dimensions of the gaps 62 in the warp moving direction
are the same.
[0047] As mentioned above, in case that the air flow constraining members 52 and 54 projecting
toward the cloth fell 26 outside the range of the warp shedding 18 and extending in
the weft inserting direction are provided respectively at the cap 34 of the reed 20
and the reed holding member 38, uprising of the air within the warp shedding 18 is
constrained by the air flow constraining members 52 and 54, thereby constraining the
rising phenomenon of the injected water from the weft insertion nozzle 22.
[0048] Also, in case that there is a gap 62 between the cap 34 and the air flow constraining
member 52, firstly when the reed 20 moves backward (when the angle of the main shaft
is in the range from 0° to 180°) as shown by an arrow 64 in Fig. 3, the air in the
weft inserting space 24 is drawn toward the reed 20, and the weft inserting space
24 is applied negative pressure. At this time, however, the air in the space above
the reed 20 flows as shown by an arrow 66 and is taken into the warp shedding 18,
particularly into the weft inserting space 24, through the gap 62. This constrains
the weft inserting space 24 from application of negative pressure.
[0049] On the other hand, when the reed 20 moves forward (when the angle of the main shaft
ranges from 180° to 0°), the air in the weft inserting space 24 is pushed toward the
cloth fell 26 by the reed 20, and the weft inserting space 24 is applied positive
pressure. At this time, however, since the air in the warp shedding 18, especially,
the weft inserting space 24, is let out into the space above the reed 20 through the
gap 62, the weft inserting space 24 is constrained from being applied positive pressure.
[0050] Thus, since a change of the atmospheric pressure of the weft inserting space 24 is
constrained, generation of updraft such as at the time of beating by the prior art
is constrained, and a change of the atmospheric pressure in the warp moving direction
is constrained, so that the actual weft flying line is much stabilized, thereby reducing
the stopping frequency of the loom.
Embodiment 2 of Weft Insertion Stabilizer
[0051] In the weft insertion stabilizer shown in Fig. 4, the air flow constraining member
52 includes a constraining portion 70 having its original function, and a turnback
portion 72 integrally continued to the upper end portion of the constraining portion
70 and turned back above the cap 34. The turnback portion 72 opens rearward of the
reed 20 and forms a vent 74 communicating with the gap 62.
[0052] Even if the vent 74 opening rearward of the reed 20 is provided such as the weft
inserting stabilizer shown in Fig. 4, when the reed 20 moves backward in the direction
as shown by an arrow 64, as well as when the reed 20 moves forward in the opposite
direction thereto, the weft inserting space 24 is theoretically applied negative pressure
and positive pressure, respectively.
[0053] At the time of backward movement of the reed 20, however, the air outside the warp
shedding 18 is more positively and efficiently taken into the weft inserting space
24 than in case of the first embodiment by the vent 74 opening rearward of the reed
20, so that the weft inserting space 24 is more surely constrained from being applied
negative pressure.
[0054] Also, at the time of forward movement of the reed 20, the air within the warp shedding
18, in more particular, within the weft inserting space 24 is constrained from being
applied positive pressure by the vent 74 opening rearward of the reed 20, and the
updraft is constrained as well as when there is no gap 62. Thus, since the upper portion
of the reed 20 is not directly opened, generation of the updraft by the gap 62 is
constrained.
[0055] Also, since the turnback portion 72 raises the efficiency in intake of the air, the
gap 62 can be made small. Further, miniaturizing the gap 62 makes it hard for the
updraft within the warp shedding 18 to leak out, so that leaking of the updraft at
the time of forward movement of the reed 20 can be constrained to the minimum.
[0056] As a result, in the second embodiment shown in Fig. 4, a change of the air flow in
the warp moving direction is constrained, thereby much stabilizing the actual weft
flying line.
Embodiment 3 of Weft Insertion Stabilizer
[0057] In the weft insertion stabilizer shown in Fig. 5, there are arranged a plurality
of spacers 60 between the mounting face of the downside reed holding member 38 and
the turned back mounting face of the downside air flow constraining member 54, and
a plurality of gaps 62 are provided on the downside air flow constraining member 54.
The lower air flow constraining member 54 may be mounted on the reed 20, more particularly,
on the cap 36.
[0058] In the third embodiment, when the reed 20 moves forward and backward in the direction
of an arrow 76 and in the opposite direction thereto, respectively, the air outside
and inside the warp shedding 18 moves in the direction of an arrow 78 and in the opposite
direction, respectively, through the gap 62, so that the weft inserting space 24 is
constrained from being applied positive pressure and negative pressure, and the actual
flying line is much stabilized.
Embodiment 4 of Weft Insertion Stabilizer
[0059] In the weft insertion stabilizer shown in Fig. 6, the second and the third embodiments
are combined, and a plurality of gaps 62 are respectively provided in the upper and
lower air flow constraining members 52 and 54. In the fourth embodiment, the negative
pressure and positive pressure states of the weft inserting space 24 are constrained
such as in the first to third embodiments above, thereby much stabilizing the actual
weft flying line.
Embodiment 5 of Weft Insertion Stabilizer
[0060] As shown in Fig. 7 as an example, in place of the gaps 62 in the first to fourth
embodiments, a plurality of holes 80 may be formed at least in one of the upper and
lower air flow constraining members 52 and 54.
[0061] For instance, in the example shown in Fig. 7, in place of the gaps 62 in the first
embodiment, a plurality of holes 80 are formed at a position near the reed 20 of the
upper air flow constraining member 52. In this example, cutouts are formed on the
mounting side of the reed 20 of the air flow constraining member 52, and portions
enclosed by the cutouts and the cap 34 are used as the holes 80. By this, it can be
said that substantially the holes 80 are provided in the air flow constraining member
52. In the example shown in Fig. 7, the shape of each hole 80 is rectangular, but
it may be of any proper shape such as oval, elliptical, circular and the like.
[0062] In case that the holes 80 are provided in the upside air flow constraining member
52, a vent 74 opening rearward of the reed 20 by the turnback portion 72 in the third
embodiment as shown in Fig. 4 may be provided.
[0063] In the fifth embodiment, too, the same action and same effect as in the first to
fourth embodiments can be obtained.
[0064] In the example shown in Fig. 7, there is no spacer 60. However, in any of the first
to fourth embodiments, not only the gaps 62 but also the plural holes 80 in the fifth
embodiment may be formed in at least one of the upside and downside air flow constraining
members 52 and 54.
[0065] Instead of forming cutouts in the air flow constraining members 52 and 54 as in Fig.
7, it is possible to form the holes 80 in the air flow constraining members 52 and
54 in themselves. In more particular, the holes 80 are formed in the region on the
reed side, not at the intermediate position in the warp moving direction of the air
flow constraining members 52 and 54.
Embodiment 6 of Weft Insertion Stabilizer
[0066] As shown in Fig. 8 as an example, in any of the foregoing embodiments, the length
dimension in the warp moving direction of the upper or the lower air flow constraining
member 52 or 54 and the width dimension of the gaps 62 or the holes 80 may have different
values by location in the weft inserting direction.
[0067] In the embodiment shown in Fig. 8, each of the air flow constraining members 52 and
54 includes a plurality (four in the illustration) of pieces 82, 84, 86 and 88 arranged
to adjoin in the weft inserting direction. The weft is inserted from the left side
in Fig. 8.
[0068] The pieces 82 and 84 located on a weft supplying side (i.e., weft inserting side)
form the gaps 62 between the cap 34 and the pieces 82, 84 of the air flow constraining
members 52 or 54 by the spacers 60. However, the width dimension along the warp moving
direction of the gaps 62 to be formed by the piece 82 at the nearest position to the
weft supply side is larger than those formed by the piece 84. This is performed by
using the spacers 60 of different length dimensions.
[0069] The pieces 86 and 88 located on the weft arrival side are screwed directly on the
cap 34 in case of the upside, and on the reed holding member 38 in case of the downside,
without using any spacers 60.
[0070] The length dimensions (L1 - L3) along the warp moving direction of the pieces 82,
84 and 86 are the same, excepting the piece 88 which is nearest to the weft arrival
side. However, the length dimension (L4) of the piece 88 along the warp moving direction
is smaller than those of the other pieces 82, 84 and 86. Also, the gap 62 in the piece
84 on the weft arrival side is smaller than the gap 62 in the piece 82 on the weft
supply side.
[0071] The width dimensions of the gaps 62 along the warp moving direction and the length
dimensions (L1 - L4) of the pieces 82, 84, 86 and 88 are as mentioned above, so that
the length dimensions of the air flow constraining member 52 or 54 from the reed 20
(or the reed holding member 38) in the warp moving direction differ by location in
the weft inserting direction. In more particular, from the weft supply side toward
the weft arrival side, the length dimensions of the pieces 82, 84, 86 and 88 and gaps
in the warp moving direction become smaller.
[0072] In other words, the position of the air flow constraining member 52 or 54 in the
warp moving direction of the front edge on the side of the cloth fell 26 differs by
location in the weft inserting direction. In more particular, from the weft supply
side toward the weft arrival side, the above-mentioned position comes nearer the side
of the reed 20. For this reason, a cutout portion 90 is formed on the cloth fell side
of the air flow constraining member 52 or 54 on the weft arrival side in contrast
to the air flow constraining member 52 or 54 on the weft supply side, and the larger
the cutout portion 90 becomes as it comes nearer the air flow constraining member
52 or 54 on the side of the weft arrival side.
[0073] When an imaginary line parallel to the extending direction of the reed from the position
(L1 + L5) which is a distance from the cap 34 farthest away to the front edge of the
piece 82 is drawn from the piece 82, lacked spaces are formed at respective regions
corresponding to the other pieces 84, 86, 88. For instance, in case of the piece 84,
the cutout portion 90 is formed in a lacked space at the cloth fell 26 side front
edge of the piece 84 adjacent to the piece 82, by a difference of the position (L2
+ L6) shorter than the position (L1 + L5).
[0074] In the illustration, the length dimensions L1, L2 and L3 of the pieces 82, 84 and
86 are respectively 35 mm, the length dimension L4 of a piece 88 is 25 mm, and the
width dimensions L5 and L6 of the gaps 62, 62 are respectively 6 mm and 3 mm. Therefore,
the nearer the pieces 82, 84, 86 and 88 are to the weft supply side, the more projected
toward the cloth fell 26.
[0075] In other words, in this embodiment, there are two areas divided respectively according
to the weft passing range, that is, when the reed 20 advances, and when it retreats,
and at the boundary between the two regions, that is, with a position where the main
shaft angle is about 180° where the swinging direction of the reed 20 reverses as
a boundary between the two regions, the gap 62 and the hole 80 are formed on the weft
supply side of the boundary, the gap 62 and the hole 80 being enlarged toward the
weft supply side, and the cutout portion 90 exists on the weft arrival side of the
boundary, the cutout portion 90 being enlarged toward the weft arrival side.
[0076] In the embodiment shown in Fig. 8, the front end of the weft inserted from the weft
supply side passes the region on the left half side formed by the pieces 82 and 84
when the reed 20 moves backward (first half in weft insertion), and passes the region
on the right half side formed by the pieces 86 and 88 when the reed 20 moves forward
(end half in weft insertion).
[0077] In general, the weft flying force is great when the front end of the weft is flying
in the supply side region (i.e., the first half region) at the time of backward movement
of the reed 20, but the weft flying force is gradually reduced during weft insertion.
Therefore, since the weft, when the front end thereof is flying in the region on the
weft arrival side (i.e., the end half region), lowers in flying speed in the end half
region due to the gravity, the flying position of the weft tends to be displaced downward.
[0078] In the embodiment shown in Fig. 8, however, since the air is taken into the weft
inserting space 24 from the gap 62 and because of the pieces 82 and 84 on the weft
supply side, the negative pressure within the weft inserting space 24 when the weft
front end passes the first half region is effectively constrained. By this, with the
great flying force of the weft, movement of the weft flying position toward the reed
20 side is constrained.
[0079] Also, the pieces 86 and 88 in the end half region where the weft front end flies
when the reed 20 moves forward, there is no gap 62, and the front edge on the cloth
fell 26 side is more backward from the cloth fell 26 than the front edges of the pieces
82 and 84, and the cutout portion 90 is formed. Consequently, in the end half region,
an updraft of the weft inserting space 24 is slightly generated, and the weft is effectively
constrained from lowering in flying position by the updraft.
[0080] In the embodiment shown in Fig. 8, the movement of the weft flying position toward
the reed 20 is more constrained toward the weft supply side, while the nearer the
weft arrival side, the updraft is adjusted and lowering in the weft flying position
is more constrained. As a result, the actual weft flying line becomes more stable.
[0081] In either of the above embodiments, when the gap 62 or the hole 80 is positioned
greatly away from the reed 20, the air within the warp shedding 18 leaks from the
gap 62 or the hole 80 at the time of the reed's forward movement, so that the updraft
is generated in the weft inserting space 24 to cause the actual weft flying line to
vary vertically.
[0082] In particular, if the gap 62 or the hole 80 is above the weft inserting space 24,
the weft also rises by the above-mentioned updraft. Therefore, the gap 62 or the hole
80 is preferably provided at a nearest possible position to the reed 20.
[0083] In the sixth embodiment, it is possible to make only the length dimension of the
upper or lower air flow constraining member 52 or 54 in the warp moving direction
vary by location in the weft inserting direction without providing the gap 62 or the
hole 80. Also, it is possible to adjust the length dimension of the upper or the lower
air flow constraining member 52 or 54 in the weft inserting direction and the warp
moving direction, and the size of the gap 62, the hole 80 and the cutout portion 90
according to the air flow within the weft inserting space or the structure of the
loom (in more particular, beating stroke, weaving width, weft inserting timing, rotation
frequency of the loom and the like).
[0084] As mentioned above, the gap 62 or the hole 80 permitting movement of the air relative
to the weft inserting space 24 may be provided in either one of the upper and lower
air flow constraining members 52 and 54 or in both of them. The size of the gap 62
may be made adjustable by exchanging spacers having different thickness, and the size
of the hole 80 may be made adjustable by movably overlapping a member, for example,
for stopping the hole 80 with the hole 80 and fixing.
[0085] The air flow constraining member 52 or 54 may be formed by a single member, as shown
in Fig. 8, into such a shape as the length dimension of the upper or the lower air
flow constraining member 52 or 54 in the warp moving direction, and the width dimension
of the gap 62 or the hole 80 have different values by positions in the weft inserting
direction. Also, the air flow constraining member 52 or 54 may be integrally provided
with the cap 34 or 36 or the reed holding member 38.
[0086] The present invention is not limited to the above embodiments but can be variously
modified without departing from its purport.