JPH0238706B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid-jet weft storage device for a loom, and more specifically, the present invention relates to a fluid-jet weft storage device for a loom. The present invention relates to an improvement of a weft storage device that stores the weft yarn by winding it and supplies it to a main nozzle for weft insertion.

In the description of this specification, based on the movement of the weft yarn on the storage device, for convenience, the expression "upstream" is used for the side closer to the yarn supply source, and the expression "downstream" is used for the side closer to the main nozzle. use

A conventional example of the above type of weft storage device is as follows:
For example, Japanese Patent Application Publication No. 55-2595 (Patent Application No. 70007)
There are inventions. In the device of the present invention, a disk that rotates about an axis perpendicular to the drum axis is provided inside the fixed drum, and several claws are provided on the circumference of the disk so as to point toward the circumferential surface of the fixed drum. Further, the disc is configured to rotate in conjunction with the rotation of the loom using the drive shaft of the rotary yarn guide as a drive source. As the disc rotates, the claws successively appear on the circumferential surface of the fixed drum, move in the axial direction of the fixed drum (i.e. from the upstream side to the downstream side), and then sink below the circumferential surface of the fixed drum. I will do it. The weft yarn wound around the fixed drum by the rotary yarn guide is moved downstream by being actively pushed by a claw that protrudes onto the circumferential surface of the fixed drum on the upstream side and moves in the axial direction, Immediately before the downstream claw sinks below the circumferential surface of the fixed drum, jetting from the main nozzle starts, and immediately after traction is applied, the downstream claw sinks below the circumferential surface and is unwound from the fixed drum. The material is then fed to the main nozzle for weft insertion. However, this conventional example has several drawbacks as described below.

The first drawback is the occurrence of yarn coming off due to lower stabilization ballooning. That is, as mentioned above, the weft yarn wound around the fixed drum is unwound from the fixed drum for weft insertion at the timing when its downstream claw sinks below the circumferential surface of the fixed drum, but at this time, as a matter of course, Form a balloon. If ballooning becomes unstable for some reason near the end of unwinding, the weft yarn for the next weft insertion, which is wound around the fixed drum upstream of the claw on the upstream side of the unwinding section, One of the winds on the most downstream side went over the claw due to unstable ballooning and was unwound. As a result, although the weft insertion length becomes longer, there is no problem with the current weft insertion,
At the time of the next weft insertion, the amount of weft fed to the main nozzle is shortened by this one wine. Therefore, the next weft insertion will be unsuccessful, resulting in a so-called shot pick, and the loom will stop.

The second drawback is the occurrence of yarn coming off due to weft yarn breakage. The weft yarn inserted into the warp opening intersects with the warp yarn by weft beating, but in order to form the desired selvage structure, the weft yarn is appropriately tensioned between the claw on the fixed drum and the main nozzle during this weft beating. It is necessary to be present. After weft beating, this tensioned weft yarn is cut by a cutter, but immediately after this cutting, the weft yarn becomes slack on the fixed drum. In terms of timing, at this time, the claws on the upstream side of the weft threads, which are used to hang the threads wound for the next weft insertion, are almost submerged below the circumferential surface of the stationary drum. Therefore, in this case, the most downstream wind of the weft for the next weft insertion, which is wound on the fixed drum upstream of the claw, is likely to be unwound beyond the claw.

A third drawback is an increase in unwinding resistance due to an increase in the axial length of the fixed drum. As mentioned above, the axis of the disc provided with the claws is perpendicular to the drum axis. Moreover, the diameter of the disc must be large to a certain extent in order to maintain it above the peripheral surface of the stationary drum for a certain period of time while moving in the axial direction with the claw. This means an increase in the axial length of the fixed drum housing the disc. Therefore, the distance from the position where the claw is recessed from the circumferential surface of the fixed drum to the downstream end of the fixed drum becomes large.
In other words, when inserting the weft, the weft yarn is forced to come into contact with a long surface, and due to the frictional resistance and the electrostatic attraction force generated by this (especially in the case of synthetic fibers), the unwinding resistance increases, resulting in a traction force with less main noise. Therefore, it becomes impossible to stably pull out the weft yarn from the fixed drum.

A fourth drawback is the difficulty in maintenance and coordination due to the internal construction. That is, the disk is disposed within the fixed drum, and its driving source is shared by the rotary yarn guide. Now, in order to change the amount of weft yarn per one weft insertion (this is necessary, for example, when the product type changes), it is necessary to change the number of weft yarns wound around the fixed drum per one weft insertion. This requires changing the rotational speed of the rotary yarn guide. Accordingly, the rotational speed of the pawl disk, which uses the same driving source, must also be changed. In other words, it is necessary to replace and adjust various parts within the fixed drum, but this alignment adjustment is complicated due to the internal structure, and as a practical matter, it is a heavy burden for the user to perform this work. It is.

A conventional example of avoiding such inconvenience is, for example, Japanese Patent Application Laid-Open No. 56-91042 (Japanese Patent Application No. 166904-1983).
There are inventions. In the device of this invention, a cam that is linked to the rotation of the loom and a pair of levers that are swung by the cam are provided in the fixed drum, and the claws formed at the tips of these levers are attached to the fixed drum. In the straight portion, as the lever swings, the lever is projected onto the circumferential surface of the stationary drum and submerged below the circumferential surface with a predetermined phase difference between the upstream and downstream positions. In this case, the weft necessary for one weft insertion is stored between the pair of claws protruding from the circumferential surface of the fixed drum, and is unwound all at once when the downstream claw sinks below the circumferential surface of the fixed drum. However, the movement of the thread wound on these drums is not pushed by the claws. Therefore, it can be said that the movement of the weft on the fixed drum is negative compared to the above-mentioned conventional example.

Although this prior art example avoids some of the drawbacks characteristic of the previously mentioned prior art example, it still has some drawbacks as described below.

The first drawback is poor unwinding due to the manner in which the weft yarn is stored by the upstream claw. In other words, the position where the upstream claw protrudes onto the circumferential surface of the fixed drum is the boundary between the conical part and the straight part of the fixed drum, and when the upstream claw protrudes on the circumferential surface, the conical The weft yarn is first stored in the section. However, if the weft used has a long pile, has a large number of filaments, or is likely to generate static electricity, a picking phenomenon occurs between the winds of the weft. In this state, even if the upstream claw sinks below the circumferential surface of the fixed drum, the winds are difficult to separate, and the wefts suddenly loosen and move rapidly on the circumferential surface of the fixed drum.
As a result, the posture of the weft wound around the fixed drum becomes unstable, causing uneven tension between the winds, and even when the downstream claw is depressed and weft insertion is possible, the main nozzle It becomes impossible to pull the weft yarn out of the fixed drum with a small traction force.

The second drawback is damage to the yarn due to a sudden decrease in the speed of the weft during unwinding and increased consumption of power for conveying the weft. When the downstream claw sinks below the drum circumference, the weft is pulled out to the fixed drum or weft insertion by the traction force of the main nozzle, but the speed remains almost constant after reaching a certain value at the beginning of weft insertion. It becomes zero at the moment when the weft on the fixed drum disappears. In this example, yarn speed is 30m/s (approximately 100Km/h)
If the speed of the weft instantaneously drops to zero, the impact applied to the weft due to its (minus) acceleration will be considerable, and damage to the weft cannot be avoided. Even if such damage were to be avoided, the entire weft yarn that had been jetted and flying from the main nozzle would dance significantly due to the above-mentioned acceleration. Of course, from the viewpoint of the weaving effect, it is not possible to intertwine the weft threads with the warp threads in such a meandering state, so the above-mentioned dancing must be suppressed as much as possible. Therefore, it is necessary to increase and strengthen the jetting from the main nozzle and sub-nozzles to reduce the influence of the above-mentioned acceleration. This inevitably leads to increased consumption of power for weft conveyance.
Furthermore, if the jetting from the nozzle is increased and strengthened, there is a risk of yarn breakage or filament cracking in the case of weft yarns having a peculiar structure.

A third disadvantage is the reduction in product quality and increased power consumption due to the engagement of the upstream pawl with the weft thread. That is, when weft insertion is completed and the weft thread intersects with the warp thread, the upstream claw is exposed on the circumferential surface of the fixed drum, and this claw does not move in the direction of the drum axis. Therefore, the weft is engaged with this upstream tab, and the weft tension between the tab and the selvage of the fabric inevitably increases. Particularly in the case of a horizontally ribbed fabric, such as a coat-like fabric, cracks will occur in the weft yarns near the selvedges, which will impair the quality of the product. Furthermore, when the weft yarn is cut with a cutter after weft beating, the so-called spring back becomes correspondingly large due to the high weft tension. Therefore, the weft yarn dances a lot within the main nozzle, making it impossible to expect stable weft insertion. To overcome this, it is necessary to lengthen the injection time of the main nozzle and further increase and strengthen the intensity, but this also leads to an increase in power consumption. Furthermore, depending on the type of yarn, yarn breakage and filament cracking may occur.

An object of the present invention is to provide a fluid-jet weft storage device for a loom, which eliminates the various drawbacks seen in the above-mentioned two conventional examples and fully takes advantage of the passive movement of the weft on a fixed drum. There is a particular thing.

That is, in this invention, a pair of claws that appear and retract at closely related timings are provided on the circumferential surface of the fixed drum on the upstream and downstream sides in the longitudinal direction of the drum axis, and these claws are arranged closely together. The drums are moved in the longitudinal direction of the drum axis at related timings, and by the cooperation of these pairs of claws, the weft yarns of each weft insertion are stably stored and unwound on the fixed drum.

The above-mentioned movement of the claws occurs at the start of weft insertion, at the timing when the weft yarn on the fixed drum runs out when moving the yarn, and in the process of completing weft insertion, where the weft intersects with the warp and is cut by the cutter. The settings are as follows.

The present invention will be explained in more detail below with reference to embodiments shown in the accompanying drawings. In the following description, it is assumed that the amount of weft yarn used per one weft insertion corresponds to four winds on a fixed drum, but it goes without saying that the present invention can be applied to other cases as well.

Further, in each of the following figures, parts not directly related to the present invention are omitted or shown in a simplified manner.

Illustrated in FIGS. 1-4 is a first embodiment of the apparatus of the invention.

The fixed drum 1 has an upstream conical portion 1a and a downstream straight portion 1b (preferably slightly conical) that is continuous with the conical portion 1a.
An elongated hole 1c is bored in the longitudinal direction of the drum shaft from near the downstream end of the straight portion 1b to near the center of the straight portion 1b. Further, a drive shaft 2 is rotatably supported on the fixed drum 1 concentrically.

An internal frame 3 fixed to the fixed drum 1
There are two support shafts 4 perpendicular to the longitudinal direction of the drum shaft.
6 is fixedly supported. A three-pronged lever 7 is pivotally supported at the top corner of the support shaft 4, and a pawl P1 is fixedly supported at the end of the downstream arm of this lever 7 so as to face the circumferential surface of the drum. A roller 8 is rotatably supported at the end.
Further, a spring seat 9 is fixed at a suitable position on the third arm, and one end of a compression spring 11 is supported on this spring seat 9. The other end of this compression spring 11 is connected to a spring seat 12 which is firmly fitted to the internal frame 3 as shown in FIG.
Supported by. Similarly, a two-pronged lever 13 is pivotally supported at the top corner of the support shaft 6, and a pawl P2 is fixedly supported at the downstream arm end of this lever 13 so as to be directed toward the drum circumferential surface. A roller 14 is rotatably supported at the end of the upstream arm. Furthermore, a spring seat 16 is fixed at a suitable position on the upstream arm, and a compression spring 17 is attached to this.
is supported at one end. The other end of the compression spring 17 is supported by a spring seat 18 which is also tightly fitted to the internal frame 3, as shown in FIG.

In the above configuration, the pawl P1 supported by the three-pronged lever 7 on the support shaft 4 is normally located on the upstream side of the pawl P2 supported by the two-pronged lever 13 on the support shaft 6. The dimensional relationships of each part are set in .

The internal frame 3 has these support shafts 4,
A cam shaft 19 extending horizontally and parallel to 6 is rotatably supported, and two cams C1 and C2 are tightly fitted to this cam shaft 19. In the figure, only a portion of the ring portions of these cams are shown. The rollers 8 on the three-pronged lever 7 are biased by the compression spring 11 on the circumferential surface of the cam C1, and the rollers 14 on the two-pronged lever 13 are biased on the circumferential surface of the cam C2 by the biasing force of the compression spring 17. It is pressed against the surface. Therefore, when the camshaft 19 rotates, the levers 7 and 13 are driven by the respective cams C1 and C2 and rotate the support shafts 4 and 6.
Accordingly, the claws P1 and P2 move in and out of the drum circumferential surface through the elongated hole c, and move in the longitudinal direction of the drum axis. The details will be described later.

Although FIG. 4 also shows the relationship between the above-mentioned parts, the left side (ie, the upstream side) of the figure is partially expanded for ease of understanding.

Next, regarding the driving relationship of the cams C1 and C2, the first
This will be explained with reference to Figure 3. The source of this drive is a bevel gear 22 that is tightly fitted to the drive shaft 2 of the rotary yarn guide 21, and this bevel gear 22 meshes with a bevel gear 24 that is integral with the rotating shaft 23. First rotating shaft 2
A spur gear 28 is integrally formed on the other end of 3, and this spur gear 28 is connected to the spur gear 3 that is tightly fitted to a second rotating shaft 29 that is also supported by the internal frame 3.
1 and meshingly engage with each other. A bevel gear 32 is formed at the other end of the second rotating shaft 29, and this bevel gear 32 is connected to a bevel gear 33 that is tightly fitted to one end of the camshaft 19.
It is meshingly engaged with. Therefore, the rotation of the drive shaft 2 is transmitted to the camshaft 19 via the rotation shaft 23 → 29,
The cams C1 and C2 are rotationally driven.

Next, the operation will be explained. As is clear from FIG. 1, the first and second claws P1 and P2 swing along arcuate paths centered on the support shafts 4 and 6, respectively. . Therefore, the protrusion and retraction from the drum peripheral surface and the movement in the longitudinal direction of the drum axis are not performed separately, but are performed in the form of a circular arc movement in which the two are combined. More specifically, each claw moves toward the upstream side when it attempts to emerge above the drum circumferential surface, and moves toward the downstream side when it attempts to sink from the drum circumferential surface.

Figure 5 is a timing diagram showing the movements of the pawls P1 and P2, which correspond to the diagrams of the cams C1 and C2, respectively. The axis is time. Further, FIG. 6 shows the states of the claws P1 and P2 at each time point () to () in FIG. 5, and the appended arrows indicate the direction of their movement.

First, weft insertion starts at time point ().
At this point, the first pawl P1 is facing the most upstream and most advanced position, and the second pawl P2 is at a position exactly retracted below the drum circumferential surface, and is located at the position of the 4 winds on the straight part b. The weft yarn is pulled by the main nozzle and is pulled out while flying freely. In this vicinity, the first claw P1 has not yet entered the dwell at this point, and the second claw further retreats and moves downstream.

At time point (), the first and second claws P1,
Both P2 are in dwell, and the second claw P2
is located at the most downstream and most retracted position. When the dwell is completed, this second claw P2 starts moving upstream while advancing. During this time, straight section 1
The weft yarn on b is drawn out while flying freely. At this point, winding of the next weft by the rotary yarn guide 19 has already begun around the conical portion 1a on the upstream side of the first claw P1.

At time (), all four winds on the straight part 1b are pulled out, so the weft finishes its free flight and becomes tense for a moment, but at the same time, the first claw P1 is pulled out from the drum. It has started or is in the process of moving downstream while retracting. Then, the conical part 1 on the upstream side of the first claw P1
Since the weft yarn wound around a is successively moved toward the straight portion 1b, the weft yarn is loosened due to the difference in winding diameter, and the slack is pulled out through the first claw P.
That is, a restrained flight is performed. During this time, the second claw P2
continues to move upstream while advancing and eventually emerges above the drum circumference.

At time point (), the first and second pawls P1 and P2, which had been approaching each other, reach one position in the drum axis length direction, and then the first pawl P1 moves downstream while further retracting. The second claw P2 dwells for a short period of time and then begins to move downstream. As a result, the second claw P2 will inherit the weft that has been wound upstream of the first claw P1. As mentioned above, the weft yarn restraint flight starts at the time when the first claw P1 starts to lock the weft yarn (), but it can end at any time up to the above-mentioned inheritance time (). In reality, the point at which the restraint flight ends () is a straight line from the inheritance point (). Even during the above process, the winding of the weft yarn by the rotary yarn guide 21 continues.

After that, the first pawl P1 continues to move in and out and sinks below the drum circumference, and as the second pawl P2, which inherits the wind, continues to move downstream, the first pawl P1 enters the dwell. . That is, at time point (), the first claw P1 is at the most downstream side and is in a position where it has retracted and sunk below the drum circumferential surface, and the second claw P2 has moved slightly downstream from the most upstream side, and It is located above the drum circumference. During this time, the winding of the weft by the rotary yarn guide 21 continues.

Eventually, the first claw P1 finishes its dwell and begins to protrude onto the circumferential surface at a timing immediately after being wound three times on the upstream side of the second claw P2, and the second claw P2 is moving downstream. Then, for a certain period of time, both the claws P1 and P2 come out on the drum circumferential surface and are separated from each other in the longitudinal direction of the drum axis, and at this time, the next straight part 1b between the claws P1 and P2 is Four winds for weft insertion are stored in sections.

Eventually, the first pawl P1 faces the most upstream and most advanced position, and the second pawl P2 reaches a position where it sinks directly below the drum circumference, returning to the state at point (), and the next weft insertion begins. be exposed.

As is clear from the above, according to the present invention, the pair of pawls are not only moved in and out of the drum circumferential surface, but also relatively moved in the longitudinal direction of the drum axis in parallel with the pair of pawls, and the weft yarn is moved between these pawls. It is inherited. Therefore, the weft that was wound on the drum while being locked by the first pawl P1 is gently moved to the second pawl P1.
2, the weft yarns are not suddenly loosened. There, the weft yarn moves downstream with its winding posture stabilized. In this way, the weft yarn is unwound from the drum in a stable state, so weft insertion is also stable, and power consumption for weft conveyance is reduced.

Furthermore, if restraint flying is employed, the phenomenon in which the speed of the weft yarn that has been drawn out at high speed suddenly drops to zero can be alleviated, and damage to the yarn can be prevented. In addition, if the second claw P2 is moved downstream before the weft cutting point, the increase in weft tension when the weft intersects with the warp due to weft beating is suppressed, so that the nozzle can spray at low pressure and in a short time. Stable weft insertion is performed even when there is a problem, and there is no slack in the fabric. Therefore, power consumption is reduced, and inconveniences such as thread breakage and filament cracking can be avoided.

Now, as mentioned above, the device of the present invention has superior effects compared to the conventional device, but in the device of the first embodiment, the claws extend from the inside of the fixed drum onto the circumferential surface. It depends on the way the claws are installed, so to speak. Therefore, depending on the balloon conditions at the time of pulling out the weft thread or the impact at the time of cutting the weft thread, it is not possible to completely prevent the accident in which the weft thread for the next weft insertion goes over the claw.

If the weft goes over the pawl in this way, it means that the weft yarn floats outward from the drum circumference, so in order to prevent this, it is necessary to attach the pawl to the drum circumference from the outside rather than from the inside. The second embodiment of the apparatus of the present invention shown in FIGS. 7 and 8 is constructed based on this idea.

In this embodiment, cams D1 and D2 for driving the claws P1 and P2 are housed in a magazine 41 that is appropriately fixed outside the fixed drum, and the claws P1 and P2 face the fixed drum of the magazine 41. It protrudes toward the fixed drum 1 from a long hole 41a that is formed extending in the longitudinal direction of the drum axis on the lower side (lower side in the figure).

That is, a support shaft 43 is fixedly supported on the internal frame 42 of the magazine 41 and extends in a direction perpendicular to the axial direction of the fixed drum.
The book levers 44, 46 are loosely fitted. Pawls P1 and P2 are fixedly supported at one end of these levers 44 and 46 (the side closer to the fixed drum), respectively, and rollers 47 and 48 are rotatably supported at the other end, respectively. Further, spring seats 49, 51 are formed at appropriate locations on the levers 44, 46, and tension springs 53, 54 are inserted between these and a spring seat 52 fixed on the internal frame 42. ing.

The internal frame 42 further rotatably supports a camshaft 56 that extends in the same direction and parallel to the support shaft 43, and this camshaft 56 has a pawl P1,
Cams D1 and D2 for P2 are tightly fitted. 7th
In the figure, only a part of the ring of one of the cams is shown. The camshaft 56 is operatively connected to an appropriate external drive source, such as the drive shaft of the rotary yarn guide 21 (see FIG. 1), by a known method. The rollers 47, 48 are always kept in elastic pressure contact with the respective cams D1, D2 by the biasing of the springs 53, 54.

The contents and timing of the claw movements are essentially the same as those in the first embodiment shown in FIGS. 5 and 6. However, in the case of this embodiment, in relation to the drum circumferential surface, it protrudes and retracts from the inside, whereas it approaches and separates from the drum circumferential surface from the outside.

Since the tabs are always on the outside of the drum circumferential surface, the more the weft threads spread outward due to the unstable balloon, the more the engagement with the tabs increases, eliminating accidents such as going over the tabs.

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view showing one embodiment of the device of the present invention. FIG. 2: A side view showing the lever biasing structure. FIG. 3: A partially sectional plan view showing the cam drive structure. FIG. 4: A partially expanded plan view showing the structure of the main part. FIG. 5: A timing diagram showing the movement of the claw. FIG. 6; A side view schematically showing the action of the claw. FIG. 7: A partially sectional side view showing another embodiment of the device of the present invention. FIG. 8; Partial cross-sectional end view thereof. DESCRIPTION OF SYMBOLS 1... Fixed drum, 1a... Cone part, 1b... Straight part, 1c... Long hole, 2... Drive shaft, 3, 42... Internal frame, 4, 6, 43... Support shaft, 7, 13, 4
4,46...Lever, 19,56...Camshaft, C1,
C2, D1, D2...cam, P1, P2...claw, 2
1...Rotating yarn guide.

Claims (1)

[Claims] 1. A yarn guide that rotates around a fixed drum having a circumferential surface consisting of a conical part and a straight part allows the conical part to slide while winding the weft yarn around the fixed drum circumferential surface, and This is a type in which one pick of weft yarn is stored separately between a pair of claws P1 and P2, which are respectively in a position where the weft yarn can be engaged with the fixed drum and a position where it is not engaged with the weft yarn, and then the weft yarn is unraveled. A pair of levers 7, 13 whose claws P1, P2 are cam-driven and swing around support shafts 4, 6, 43 extending in a direction perpendicular to the fixed drum shaft.
46, and by swinging one lever, one claw P1 is
It is placed in the action section on the drum conical part and at the standby position downstream from this, and by swinging the other lever, the other claw moves the action section from the most upstream point of the action section of the one claw to the straight section. At the standby position downstream from this,
The swing of both levers is set by a cam so that the two claws intersect in the overlapping area of the action sections of the two claws at the timing when the weft thread is transferred from one claw to the other claw. A fluid jet weft storage device for looms. 2. The lever according to claim 1, wherein one lever is driven by a cam so that one claw P1 moves from the upstream side toward a position where both claws intersect at timings before and after the start of weft locking. Device. 3. The device according to claim 1 or 2, wherein the other lever is driven by a cam so that the other claw P2 moves downstream from the intersection position of the two claws at a timing before weft cutting.