Weft tension applying device

Abstract

To provide a weft tensioning device that can apply tension of sufficient strength to weft by a simple configuration.SOLUTION: A stretch mechanism has a weft traveling passage 50 extending along a weft guide passage, an air blow nozzle 63 that injects air in a direction along the weft traveling passage 50, and a stretch air injection port 74 for injecting air in a different direction from the direction along the weft traveling passage 50. The air blow nozzle 63 introduces a weft 23 to the weft traveling passage 50 by injecting air. The stretch air injection port 74 injects air to the weft 23 introduced into the weft traveling passage 50.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a weft tensioning device for an air jet loom. [Background technology]

[0002] In order to weave high-quality fabrics using an air jet loom, it is necessary to apply an appropriate tension to the inserted weft yarn and prevent it from loosening. A weft tensioning device for applying tension to the weft yarn is known, as described in Patent Document 1. The weft tensioning device described in Patent Document 1 applies tension to the weft yarn by injecting air from an air injection nozzle provided at the rear of the air jet loom toward the front of the air jet loom, thereby bending the weft yarn forward and introducing it into a stretch pipe provided at the front of the air jet loom. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-285713 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the weft tensioning device described in Patent Document 1 applies tension to the weft by bending the weft only in one direction, from the rear to the front of the air jet loom, and therefore has the problem of not being able to apply sufficient tension to the weft.

[0005] The present invention has been made to solve the above-mentioned problems, and has an object to provide a weft tension applying device that can apply a sufficient amount of tension to a weft yarn with a simple configuration. [Means for solving the problem]

[0006] The weft tensioning device according to the present invention is for an air jet loom that inserts a weft along a weft guide passage provided in a reed. At the downstream end of the weft The weft yarn passing passage is provided in front of the reed and extends along the weft yarn guide passage, and the weft yarn passing passage is provided with a first air injection unit that injects air in a direction along the weft yarn passing passage, and a second air injection unit that injects air in a direction different from the direction along the weft yarn passing passage. The first air injection unit injects air to introduce the weft yarn into the weft yarn passing passage, and the second air injection unit Between the yarn inlet and the yarn outlet inside the weft passage, Air is sprayed onto the weft yarn introduced into the weft yarn flying passage.

[0007] In addition, the weft thread passage is A loom that protrudes from the rear to the front of the air jet loom between the yarn inlet and the yarn outlet. It may have a bent portion. The second air ejection section may eject air at the bent portion. Furthermore, the first air injection unit may stop injecting air after the second air injection unit has injected air. Furthermore, the first air injection unit may continue to inject air after the second air injection unit has injected air. [Effects of the Invention]

[0008] According to the weft tension applying device of the present invention, the first air injection section injects air in a direction along the weft flight path to introduce the weft into the weft flight path, and the second air injection section injects air at the weft introduced into the weft flight path in a direction different from the weft flight path, so that a sufficiently strong tension can be applied to the weft with a simple configuration. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing an outline of a loom according to an embodiment of the present invention; [Figure 2] FIG. 2 is a right side view showing the weft guide passage shown in FIG. [Figure 3] FIG. 2 is a plan view showing an outline of the loom shown in FIG. [Figure 4] FIG. 2 is a perspective view showing the stretching mechanism shown in FIG. 1. [Figure 5] FIG. 4 is a bottom view of the stretching mechanism shown in FIG. 3. [Figure 6] FIG. 4 is a plan end view of the upper portion of the stretching mechanism shown in FIG. 3. [Figure 7] 1 is a front end view of the upper part of the stretching mechanism showing the operation of the mechanism according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing an outline of a loom according to an embodiment of the present invention, illustrating the configuration of the right end of the air jet loom. FIG. 2 is a right side view showing the weft guide passage shown in FIG. 1. A modified reed 10 is provided above a slay 13 extending in the direction of travel of the weft in the air jet loom. The modified reed 10 is formed to extend in the direction of travel of the weft, and a weft guide passage 11 through which the weft travels is formed in front of it. The weft travels through the weft guide passage 11 from upstream to downstream along the air flow due to the air injection action of main and sub-nozzles for weft insertion (not shown). The modified reed 10 constitutes a reed.

[0011] A stretching mechanism 40 for applying an appropriate tension to the weft yarn to prevent it from loosening is provided in front of the modified reed 10, i.e., the front of the air jet loom. A rectangular tubular weft passage 50 is formed in the upper mechanism 41 of the stretching mechanism 40. The weft passage 50 is disposed in the weft guide passage 11 and extends along the weft guide passage 11. The weft passage 50 has a yarn inlet 51 on the upstream side through which the weft yarn is introduced and a yarn outlet 52 on the downstream side through which the weft yarn is discharged. Therefore, the weft passing through the weft guide passage 11 of the modified reed 10 can pass through the weft passage 50. The stretching mechanism 40 is made of an appropriate material such as resin or metal. The stretching mechanism 40 constitutes a weft tension applying device.

[0012] A protrusion 42 is formed on the upper mechanism 41 of the stretching mechanism 40, protruding from the main body of the stretching mechanism 40 toward the front of the air jet loom. To the left of the protrusion 42 when viewed from the front of the air jet loom, i.e., on the upstream side in the weft flying direction, an air blow hole 60 is formed for blowing air onto the weft in the weft flying passage 50. An air blow hose 62 is connected to the air blow hole 60 via an air blow joint 61. The air blow hose 62 is connected to an air supply source (not shown) in the factory via a well-known air valve (not shown).

[0013] A stretch air hole 70 is formed in the mechanism lower part 43 of the stretch mechanism 40 to spray stretch air onto the weft yarn in the weft yarn flying passage 50. A stretch air hose 72 is connected to the stretch air hole 70 via a stretch air joint 71. The stretch air hose 72 is connected to an air supply source (not shown) in the factory via a well-known air valve (not shown). The air jet loom is also provided with a control device (not shown) that controls the supply of air to the air blow hole 60 and the stretch air hole 70.

[0014] 3 is a plan view showing the outline of the loom shown in FIG. 1, showing the modified reed 10 and the stretching mechanism 40 in a horizontal cross-sectional view along the weft guide passage 11. The modified reed 10 has a plurality of reed dents 12 arranged at equal intervals perpendicular to the weft travel direction. Between each reed dent 12, warp yarns 21, which together with the weft yarn 23 form the woven fabric 31, and selvedge yarns 22, which together with the weft yarn 23 form the waste selvedge 32, pass. The weft yarn 23 travels through the weft guide passage 11 of the modified reed 10 and a weft travel passage 50 disposed within the weft guide passage 11. A well-known optical weft detector 14 is provided on the right side of the stretching mechanism 40 as viewed from the front of the air jet loom, i.e., downstream in the weft travel direction, to detect long picks and break-outs of the weft yarn 23.

[0015] FIG. 4 is a perspective view of the stretching mechanism shown in FIG. 1. As shown in FIG. 4, the air blow hole 60 of the stretching mechanism 40 opens on the left side of the protrusion 42 of the stretching mechanism 40. Meanwhile, an air vent hole 53 opens on the upper surface of the weft yarn flying passage 50. The air vent hole 53 is connected to the weft yarn flying passage 50. The stretching mechanism 40 has a stretching air passage 73 extending vertically inside. The weft yarn flying passage 50 is connected to the stretching air passage 73. The stretching air passage 73 is connected to the stretching air hole 70 of the mechanism lower part 43. Therefore, the stretching air hole 70 is configured to communicate with the air vent hole 53 via the stretching air passage 73 and the weft yarn flying passage 50. FIG. 5 is a bottom view of the stretching mechanism shown in FIG. 3. As shown in FIG. 5, the stretching air hole 70 opens at the center of the bottom surface of the mechanism lower part 43.

[0016] Fig. 6 is a plan end view of the upper part of the stretching mechanism shown in Fig. 3. As shown in Fig. 6, the weft yarn passage 50 of the stretching mechanism 40 has a bent portion 54 inside the passage, near the protruding portion 42 between the yarn inlet 51 and the yarn outlet 52. The bent portion 54 is trapezoidally formed so as to protrude from the rear side to the front side of the air jet loom. Here, if the width of the weft yarn passage 50 is taken as the horizontal width along the front-to-rear direction of the air jet loom, the width of the weft yarn passage 50 at the bent portion 54 is narrower than the width of the weft yarn passage 50 at the yarn inlet 51 and the yarn outlet 52. As a result, the weft yarn passage 50 is formed so that its center line bends toward the front of the air jet loom at the bent portion 54.

[0017] At the bent portion 54, a stretch air outlet 74 connected to a stretch air passage 73 (see FIG. 4) opens substantially vertically upward at the narrowest part of the weft yarn flying passage 50. That is, the stretch air hole 70 communicates with the stretch air outlet 74 via the stretch air passage 73. The stretch air outlet 74 and the air vent hole 53 open so as to substantially overlap when viewed vertically. The stretch air outlet 74 constitutes a second air injection section.

[0018] An air blow nozzle 63 having an air blow hole 60 as an air inlet is formed in the protruding portion 42. The air blow nozzle 63 extends along the direction of the inner wall of the weft yarn flying passage 50 between the bent portion 54 and the yarn outlet 52, up to the area between the bent portion 54 and the yarn outlet 52. The air blow nozzle 63 has an air blow outlet 64 at its tip. The air blow outlet 64 opens to the right of the bent portion 54, i.e., on the yarn outlet 52 side, between the bent portion 54 and the yarn outlet 52, of the weft yarn flying passage 50. The air blow outlet 64 also has a gap between the inner wall between the bent portion 54 and the yarn outlet 52, allowing the weft yarn 23 to pass through the gap. The air blow nozzle 63 constitutes a first air injection unit.

[0019] Next, the operation of the stretching mechanism 40 in this embodiment will be described. As shown in Figure 3, when the weft thread 23 is inserted, the action of the air sprayed from the main jet nozzle and the sub-jet nozzle causes the weft thread 23 to travel through the weft guide passage 11 of the modified reed 10 from the left side of the loom to the right side, i.e., from upstream to downstream of the air flow from the main nozzle. After the weft thread 23 has traveled to the position of the selvage yarn 22, the weft thread 23 is introduced into the weft traveling passage 50 of the stretching mechanism 40 through the yarn inlet 51.

[0020] As shown in Figure 4, when the weft yarn 23 is introduced from the yarn inlet 51 in the direction of arrow A, the air valve is opened by the control device, and air is supplied from the air supply source to the air blow hole 60 in the direction of arrow F via the air blow hose 62 (see Figure 3).

[0021] The air supplied to the air blow hole 60 in the direction of arrow F is sprayed in the direction of arrow G from an air blow outlet 64 at the tip of the air blow nozzle 63, as shown in Fig. 6. That is, the air blow nozzle 63 sprays air in a direction along the weft yarn flying passage 50, more specifically, in a direction along the inner wall between the bent portion 54 and the yarn outlet 52. Due to this air blow, when the weft yarn 23 is introduced into the yarn inlet 51, the weft yarn 23 is sucked in the direction of arrow B toward the yarn outlet 52. Therefore, the weft yarn 23 is smoothly introduced into the yarn inlet 51.

[0022] Next, the weft yarn 23 travels in the direction of arrow B while bending toward the front of the air jet loom at the bending portion 54. Therefore, the weft yarn 23 travels while making contact with the bending portion 54. A first tension is applied to the weft yarn 23 due to the bending at the bending portion 54 and the friction with the bending portion 54 caused by the contact. After the tip of the weft yarn 23 passes through the bending portion 54 and is led out of the yarn outlet 52, the air valve is opened by the control device, and stretch air is supplied from the air supply source via the stretch air hose 72 (see FIG. 3) to the stretch air hole 70 shown in FIG. 4 in the direction of arrow C. The stretch air supplied to the stretch air hole 70 flows upward through the stretch air passage 73 in the direction of arrow D. The stretch air is then ejected substantially vertically upward from the stretch air ejection nozzle 74 shown in FIG. 6. That is, the stretch air ejection nozzle 74 ejects the stretch air in a direction different from the direction along the weft yarn traveling passage 50.

[0023] The timing of this stretch air injection is preferably the timing when the weft yarn 23 has flown and is fully stretched. After that, the stretch air flows out mainly from the air vent holes 53 (see FIG. 4) on the upper side of the weft yarn flying passage 50.

[0024] At the bending portion 54, the weft yarn 23 receives stretch air jetted from the stretch air jet nozzle 74 in a substantially vertically upward direction different from the direction along the weft yarn flying path 50. As a result, as shown in Fig. 7, the weft yarn 23 is bent in the direction of arrow H, which is a substantially vertically upward direction, and is pressed against the upper surface of the inner wall of the bending portion 54 and the corner 53a of the air vent hole 53. Therefore, a second tension is applied to the weft yarn 23 due to friction between the weft yarn 23 and the upper surface of the inner wall of the bending portion 54 and friction between the weft yarn 23 and the corner 53a of the air vent hole 53.

[0025] The weft yarn 23 is bent at the bending portion 54 while flying, thereby applying a first tension to the weft yarn 23, and the stretch air presses the weft yarn 23 in the direction of arrow H, thereby applying a second tension to the weft yarn 23, thereby applying a strong tension to the weft yarn 23. Therefore, compared to when only one of the first tension and the second tension is applied to the weft yarn 23, slack in the weft yarn 23 can be suppressed and weaving quality can be improved.

[0026] After the stretch air is sprayed from the stretch air nozzle 74, the control device stops the supply of air to the air blow holes 60. This stops the air blow from the air blow nozzle 64. This reduces air consumption and reduces the cost of the weaving process.

[0027] Another method for applying tension to the weft yarn 23 is to blow air more strongly from the air blow nozzle 63 shown in Figure 6 in the direction along the weft yarn flying path 50. However, if a covering yarn is used for the weft yarn 23, the cover yarn of the weft yarn 23 may separate and fly ahead, leading to its exit from the yarn outlet 52. In this case, as shown in Figure 3, the weft detector 14 for the weft yarn 23, which is located to the right of the stretch mechanism 40, may detect the separated cover yarn, which may result in excessive detection of long picks and blow-outs. Therefore, this method may result in unnecessary stoppages in the weaving process, increasing weaving costs.

[0028] On the other hand, according to this embodiment, since the air blow nozzle 63 does not blow strong air in the direction along the weft yarn flying path 50, separation of the covering yarn is suppressed even if a covering yarn is used for the weft yarn 23. This reduces the probability of unnecessary stoppages in the weaving process.

[0029] Furthermore, a weft tensioning device for an air jet loom is known that applies tension to the weft by bending the weft toward the rear of the air jet loom, i.e., the back side of the reed. However, in such a weft tensioning device, bending the weft toward the back side of the reed pulls the warp, bending it toward the back side of the reed and forcing the reed dents aside, which can damage reeds with particularly high density dents.

[0030] On the other hand, according to this embodiment, the air blow nozzle 63 injects air in a direction along the weft yarn flying passage 50, and the stretch air injection port 74 injects air in the direction of arrow H, which is substantially vertically upward, at the weft yarn introduced into the weft yarn flying passage 50. Therefore, the yarn does not push aside the reed dents of the modified reed 10, and damage to the modified reed 10 can be prevented.

[0031] As described above, the stretching mechanism 40 according to this embodiment is provided in front of the modified reed 10 of an air jet loom that inserts the weft 23 along the weft guide passage 11 provided in the modified reed 10, and includes a weft passage 50 extending along the weft guide passage 11, an air blow nozzle 63 that sprays air in a direction along the weft passage 50, and a stretch air outlet 74 that sprays air in a direction different from the direction along the weft passage 50. The air blow nozzle 63 sprays air to introduce the weft 23 into the weft passage 50, and the stretch air outlet 74 sprays air at the weft 23 introduced into the weft passage 50, so that a sufficient tension can be applied to the weft 23 with a simple configuration.

[0032] Furthermore, according to the stretching mechanism 40 of this embodiment, the weft thread flying passage 50 has a curved portion 54, so that strong tension can be applied to the weft thread 23 due to friction between the weft thread 23 and the curved portion 54.

[0033] Furthermore, according to the stretching mechanism 40 of this embodiment, the stretch air jet nozzle 74 jets air at the bending portion 54. As a result, the weft yarn 23, which is bent toward the front of the air jet loom at the bending portion 54, is bent in the direction of arrow H, which is substantially vertically upward, and is pressed against the upper surface of the inner wall of the bending portion 54 and the corner 53a of the air vent hole 53, generating a large frictional force. This allows even stronger tension to be applied to the weft yarn 23.

[0034] Furthermore, according to the stretching mechanism 40 of this embodiment, the air blow nozzle 63 stops spraying air after the stretching air outlet 74 sprays air, thereby reducing air consumption and reducing the cost of the weaving process.

[0035] In this embodiment, the air blow nozzle 63 stops blowing air after the stretch air jetting port 74 jets air. However, if the weft yarn 23 is a yarn that is difficult to separate, such as a filament yarn, the air blow nozzle 63 may continue blowing air after the stretch air jetting port 74 jets air.

[0036] As described above, according to the stretching mechanism 40 of this embodiment, the air blow nozzle 63 continues to inject air after the stretch air injection port 74 has injected air, so that in addition to the first tension and second tension described above, a third tension is applied to the weft yarn 23 by air blowing in the direction of the weft yarn flying passage 50, thereby making it possible to apply a stronger tension to the weft yarn 23.

[0037] In order to increase the amount of stretching of the flying weft yarn 23 and to extend the time for which the weft yarn 23 is fully stretched, air blowing from the air blow nozzle 63 may be continued after air is jetted from the stretch air jetting port 74. Furthermore, an additional air blowing nozzle may be provided at a position different from the air blowing nozzle 63 to perform additional air blowing.

[0038] Furthermore, although the stretch air outlet 74 is open in a substantially vertically upward direction, it may be open in any other direction as long as it is a direction different from the air blow direction of the air blow nozzle 63. For example, the stretch air outlet 74 may be open toward the front of the air jet loom, i.e., in a direction away from the modified reed 10. This allows the stretch mechanism 40 to spray stretch air in a direction different from the direction along the flight path of the weft yarn 23, thereby applying tension to the weft yarn 23, just like in this embodiment. [Explanation of symbols]

[0039] 10 Deformed reed (reed), 11 Weft guide passage, 23 Weft, 40 Stretching mechanism (weft tensioning device), 50 Weft running passage, 54 Bending section, 63 Air blow nozzle (first air injection section), 74 Stretch air injection port (second air injection section).

Claims

1. 1. A weft tensioning device for an air jet loom that inserts a weft along a weft guide passage provided in a reed, the weft tensioning device being provided in front of the reed at a downstream end of the reed in a direction in which the weft travels, a weft running passage extending along the weft guide passage; a first air injection unit that injects air in a direction along the weft flying path; a second air injection unit that injects air in a direction different from the direction along the weft flying path; Equipped with the first air injection unit injects air to introduce the weft into the weft flying passage, The second air injection unit is a weft tension imparting device that injects air onto the weft introduced into the weft flying passage between a yarn inlet and a yarn outlet inside the weft flying passage.

2. 2. The weft tension applying device according to claim 1, wherein the weft passage has a bent portion that protrudes from the rear side to the front side of the air jet loom between the yarn inlet and the yarn outlet.

3. The weft tension applying device according to claim 2, wherein the second air injection section injects air at the bent portion.

4. The weft tension applying device according to any one of claims 1 to 3, wherein the first air injection unit stops injecting air after the second air injection unit has injected air.

5. The weft tension applying device according to any one of claims 1 to 3, wherein the first air injection unit continues to inject air after the second air injection unit has finished injecting air.

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