JPH0583647B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a weft insertion device for a flexible band rapier loom, and more specifically relates to a weft insertion device for a flexible band rapier loom.
This invention relates to a flexible band rapier loom that is capable of stably inserting weft at speeds of 350 rpm or higher.

(Prior art and its problems) In a flexible band rapier loom, the flexible band is in an extended state during weft insertion, and on the other hand, when weft insertion is finished, it is wound around the outer circumferential surface of the band wheel, or the flexible band is wrapped around the bow-shaped band provided at the lower side of the band wheel. The action of being stored in the sheath is repeated. At this time, the flexible band itself has the basic function of being wound around the band wheel at the end of weft insertion, and then being stretched during weft insertion. The effect of the body's own weight is added. In other words, the force acting on the flexible band by the weft gripping body is the inertia of the weight of the weft gripping body itself at the transition point of acceleration from the state where the band is wound around the band wheel to the stretched state for weft insertion. Due to the force, when the flexible band is stretched, there is a forward bending phenomenon, while when the band is wound around the band wheel, there is a floating phenomenon (hereinafter referred to as the swinging phenomenon, the mode of which is shown in Figs. 8 and 9), and the weft gripping body In the vicinity of the attachment part, bending stress is always generated due to this swinging phenomenon for each weft insertion.

By the way, in recent years, due to demands for improved productivity, there has been a desire for flexible rapier looms to have higher speeds than the conventionally popular loom rotation speed of around 240 rpm to 350 rpm or more. As the speed increases, this oscillation phenomenon of the weft yarn conveying body becomes more noticeable, and the suitability of the flexible band to cope with the increase in speed has become a new problem.

Conventionally, attempts have been made to increase the thickness and width of the band in order to solve the running stability of the weft conveyor caused by this oscillation phenomenon, but simply increasing the thickness and width of the band will cause the band to elongate. It is true that the bending rigidity of the band is increased, which has a positive effect on the running stability of the weft conveyor, but on the other hand, when winding the band, the bending rigidity of this band is high, so the sheath part that houses the band has a negative effect. New problems have arisen, such as increased contact pressure between the band and the sheath, which causes the sheath and the band to generate abnormal heat, resulting in significant wear and adversely affecting the lifespan of the band.

Therefore, in order to solve this drawback, we installed a metal 400mm to 500mm wire to increase rigidity near the attachment part of the weft conveyor.
A method has been proposed in which a reinforcing member with a length of mm is attached, while the thickness and width of the band are almost the same as before (Japanese Patent Laid-Open No. 163235/1983). Although this device certainly has good running stability of the weft conveyor,
Attaching a 500mm-long reinforcing member to the band means that the width of the machine base relative to the weaving width of the cloth becomes longer by twice this length, and as a result, related parts become longer and the machine becomes longer. The disadvantage was that the installation area of the stand became larger, which increased equipment costs.

(Purpose) Therefore, the present invention aims to eliminate the above-mentioned drawbacks, and its purpose is to
It is an object of the present invention to provide a weft insertion device for a flexible band rapier loom, which can reduce the vibration of the weft conveyor as much as possible and perform stable weft insertion even when the speed is increased to 350 rpm or more.

(Means for Solving the Problems) In order to achieve the above object, the present invention first attaches a plurality of flexible bands and engages each band in order to increase the rigidity near the weft conveyor attachment part when the flexible band is stretched. On the other hand, when winding up a flexible band, the engagement of each band is released, and each band is separated and rolled into an independent storage source, thereby reducing the flexibility of the flexible band itself. It is characterized by being configured to do the same thing as a band.

(Function) When the flexible band is driven by the band wheel and extends, the protrusions and holes provided on each of the plurality of flexible bands engage with each other, so that the flexible band becomes an integral structure and the rigidity increases as a whole.

(Example) An example of an apparatus for carrying out the present invention will be described in detail with reference to the drawings. In FIG. Upper and lower two layers of flexible pads 2 and 3 made of FRP or CFRP are fixed with bolts 4 with a certain gap in between. As shown in FIG. 4, the upper flexible band 2 (hereinafter simply referred to as the upper band) is provided with a group of holes 2a at regular intervals in the longitudinal direction. On the other hand, the lower flexible band 3 (hereinafter simply referred to as the lower band)
As shown in FIG. 5, there are provided a group of projections 3a that engage with the holes 2a of the upper band 2 in the longitudinal direction, and a group of holes 3b are bored between the projections 3a. There is. Reference numeral 5 denotes a band wheel fixed to a rotary shaft 6 driven by a drive source of the loom main body via a suitable transmission means, and the band wheel has projections on its outer peripheral surface that engage with the holes 3b of the lower band 3. A group 5a is provided, and these protrusions serve as a source of movement for the flexible band. 7 is the lower band 3
is an arcuate sheath that serves as a storage source when the band is rolled up, and the storage sheath is disposed at an appropriate position below the band wheel 5. Reference numeral 8 denotes a storage sheath which controls the storage of the upper band 2 when it is rolled up. It is placed at an appropriate position outside the locus drawn by. 9
are the sides of the upper and lower bands 2 and 3 and the upper band 2
A band holder that regulates and guides the upper surface and the bottom of the lower band 3, the band holder has a cross-section shaped like the letter 〓, as shown in FIG. 2, and is disposed above the band wheel 5. has been done.

Note that 10 is a raceway.

An example of a device for carrying out the present invention is constructed as described above, and its operation will be explained next. In FIG. At this time, the flexible band attached to the weft conveyor 1 is pressed by the band presser 9, and the lower band 3 is first pressed against the outer peripheral surface of the band wheel 5. The upper band 2 is stored in a lower band storage sheath 7 provided at the lower part of the upper band 2.
is bent slightly away from the arc portion of the lower band 3, and then stored in the upper band storage sheath 8. Therefore, here, the lower band 3 and the upper band 2 are separated from substantially above the center line 0-0' of the band wheel 5 and are in the unwound state. From this state, when the band wheel 5 is rotated counterclockwise, the protrusion 5a on the outer peripheral surface of the band wheel 5 moves into the hole of the lower band 3.
It engages with group b, becomes a driving force for the lower band 3, and causes the band to extend on the raceway 10 as shown in FIG. For this reason, the upper band 2 also extends at the same time as the lower band 3 since its tip is fixed to the weft conveyor 1 by the bolt 4. At this time, from the location of the band presser 9, lower band 3
Since the protrusions 3a provided on the upper surface engage with the holes 2a of the upper band, when the flexible band is stretched, the upper and lower two layers of the band are connected to form an integral structure, and the rigidity of the band itself is reduced. This will be enhanced compared to the case of only one band. As a result, the bending rigidity of the flexible band is increased, so that the oscillation phenomenon of the weft yarn conveying body 1 remains almost the same as in the past even when the loom rotation speed is increased to 350 rpm or higher.

On the other hand, when the weft is received from the weft conveyor (not shown) carried from the opposite end of the loom at the center of the width of the woven fabric, the band wheel 5 rotates clockwise in the opposite direction to that described above. For this reason, the flexible band
The state shown in the figure becomes involved in the state shown in FIG. At this time, the lower band 3 is wound up on the lower band storage source 7, while the upper band 2 is wound around the central part 0- of the band wheel 5.
At around 0', the engagement between the protrusion group 3a of the lower band 3 and the hole group 2a of the upper band is released, and the lower band 3 is stored in the upper band storage sheath 8 curved above the lower band 3. As a result, the upper and lower two layers of flexible bands are wound up separately.

Figure 6 shows a case where the flexible bands attached to the weft conveyor are perpendicular to the warp group, and the two bands 12 and 13 are attached parallel to the longitudinal center line 0-0' of the weft conveyor. This is an example. In this case, since the thickness t of the band is large, the bending rigidity is increased, which is advantageous for reducing the oscillation phenomenon when the band is stretched. At this time, although not shown, the band storage source is disposed so as to be wound horizontally with respect to the raceway surface.

FIG. 7 shows an example in which the storage source 14 for storing the upper flexible band 2 is arranged above the band wheel 5, which is the storage source for storing the lower flexible band 3, from the extension line of the raceway. It is. In this case, the protrusion group 3a of the lower band 3 and the hole group 2 of the upper band 2, which are the engagement members between each band.
The mesh and engagement with a is extremely good. This is because, when the upper and lower bands are engaged, the repulsive force against the bending action that occurs when the upper and lower bands are respectively wound into the storage source acts in the direction in which the protrusions and holes of the bands engage.

(Effects) As described above, the present invention attaches a plurality of flexible bands to one weft conveying body, and when the flexible bands are stretched, each flexible band is made into an integral structure using an engaging member provided between the flexible bands. Since the rigidity is increased, compared to conventional weft insertion devices, even when the loom speed exceeds 350 rpm, it is possible to avoid the vibration phenomenon caused by the weight of the weft conveyor and perform stable weft insertion.

[Brief explanation of the drawing]

FIG. 1 is a front view of the main parts including a partially cut-out part showing an example of an apparatus for carrying out the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. This shows a front view of the flexible band when it is stretched, and Figure 4A is a plan view of the main part of the upper band.
Figure 4B is a sectional view taken along line A in Figure 4A, Figure 5A is a plan view of essential parts of the lower band, Figure 5B is a sectional view taken along line A in Figure 5A, and Figure 6A is a sectional view taken along line A in Figure 4A. FIG. 6B is a front view of FIG. 6A, and FIG. 7 is a main part plan view including a partial cutout showing another example of an apparatus for implementing the present invention. The partial front view, FIGS. 8 and 9 are explanatory diagrams showing the operating state of a conventional weft insertion device. 1... Weft conveyor, 2... Upper flexible band,
2a...hole, 3...flexible band, 3a...protrusion, 5...band wheel, 7...lower band storage sheath, 8...
Upper band storage sheath.

Claims (1)

[Claims] 1. A plurality of flexible bands are attached to one weft conveying body, and these bands are driven by a band wheel which is rotated in forward and reverse directions alternately as a drive source, and when winding up the flexible band, each flexible band is operated separately and independently. In a flexible band rapier loom having a storage source, a plurality of protrusion groups are provided on the circumferential surface of one of the plurality of flexible bands, and a plurality of protrusion groups are provided on the circumferential surface of one of the plurality of flexible bands, and a plurality of protrusion groups are provided on the circumferential surface of another flexible band in correspondence with this protrusion group. A plurality of hole groups are provided on the circumferential surface, and when the flexible band is stretched, the protrusion group of the flexible band and the hole group engage with each other, so that the plurality of flexible bands form an integral structure. Features: Flexible band rapier loom weft insertion device.