US3324897A - Slide valve controlled pneumatic weft holding device - Google Patents

Description

June 13, 1967 w RAWER 3,324,8 7

SLIDE VALVE CONTROLLED PNEUMATIC WEF'P HOLDING DEVICE Filed May 18, 1965 2 Sheets-Sheet l INVENTOR WALTER RAiNER Rodi june H3, 3967 w. RAENER 3 3 SLIDE VALVE CUNTROLLED PNEUMATIC WEF'I HOLDING DEVICE Filed May 18, 1965 2 Sheets-Sheet 2 INVENTOQ WA LTER WAINER United States l at'ent 6 3 324,897 SLIDE VALVE CONTliQLLElD PNEUMATIC WEFT HOLDINGDEVICE Walter Rainer, Dornhirn, Vorarlherg, Austria, assignor to Adolph Saurer Ltd, Arbon, Switzerland Filed May 18, 1965, Ser. No. 456,724 Claims priority, application Austria, May 21, 1964, A 4,417/64 2 Claims. (Cl. 139170.3)

This invention relates to looms, and more particularly to weft holding means for use on drop box looms and the like. I

Looms provided with shuttle changing mechanism such as drop boxes are controlled by pattern cards to convey into the plane of the lay the particular shuttle compartment which contains the shuttle for the desired color. Shuttle changing mechanisms of this kind are known to be subject to the serious problem that especially at the time of shuttle change, the several wefts become entangled, with the result that on picking, not only the weft conveyed into the plane of the lay is introduced into the web, but also wefts deriving from adjacent, supposedly inactivated shuttles are introduced to create entanglement. These stray wefts must thereafter be removed which necessitates a troublesome and time consuming operation. The provision of a drop box loom free from this grave drawback, therefore, has long been a desideratum in this art a long time.

A promising approach to a solution of this problem 1s provided by the present invention in a pneumatic devlce which includes suction ports disposed in the shuttle compartments on the side of the box facing the lay, and wherein the conduits leading to the individual ports originated at individual openings are arranged in a vacuum distribution chamber. This pneumatic device is designed to maintain the wcfts extending from the shuttle compartments to the web, under tension, so that a mutual entanglement of the wefts in this region is effectively avoided. While on the whole satisfactory, this arrangement suffers from the disadvantage that inasmuch as the suction effect is imparted to and maintained at all the suction ports at all times, a very material suction output is required which can be delivered only by a powerful and hence, costly, vacuum pump.

It is a principal object of the invention to provide a device for preventing weft entanglement as encountered in shuttle changing drop box looms, which, while utilizing a pneumatic principle as proposed in the prior art, materially improves the known system by materially reducing the size and cost of the vacuum installation required.

Other objects, and the manner in which the same are attained, will become apparent as this specification proceeds.

In implementation of the afore-noted objective, the present invention contemplates providing the vacuum distribution chamber of a shuttle changing drop box loom with a distributor valve arranged in said chamber for displacement relative thereto, and designed to close certain openings of the distributor chamber in accordance with the position of the drop box relative to the plane of the lay.

The invention is based on the discovery that without impairing in the least the efiiciency of the pneumatic system, some of the suction ports on the drop box may be closed, so as to afford a very material saving in the pump capacity required, the choice of the ports thus closed being dictated by the position of the drop box relative to the lay. Suction ports which can always be closed are the ports in the shuttle compartment which is disposed in the plane of the lay.

The preferred embodiment of the invent-ion includes upper and lower suction ports, preferably disposed in the side wall, for each shuttle compartment; the upper port may be omitted in the top compartment, and the lower port may be dispensed within the bottom compartment. I have found that dependent on the position of the drop box relative to the lay, only one of the pair of ports in each shuttle compartment is actually needed to hold and maintain under tension, the weft deriving from the shuttle in the compartment. More particularly, I have found that the only suction ports which are required to be operational, i.e. which must be connected with the pump so as to function as an active, elfective suction means, are the lower suction ports of the compartments disposed above the plane of the lay, and the upper suction ports of the compartments disposed below the plane of the lay. The remaining suction ports may be shut oil? from the source of vacuum whereby the suction output required is very materially reduced.

This selective shut-off or closing of part of the suction ports of a shuttle changing drop box loom is achieved, according to the present invention, by providing the vacuum distribution chamber with openings which are spaced from one another by the same distance, a suction conduit leading from each of said openings to one of the suction ports in the shuttle compartments of the drop box of the loom, and by providing a distributor valve arranged for displacement relative to the vacuum distributor chamber, this valve having openings which in the center are spaced from one another by three times the distance between the openings in the distributor chamber, and which above and below the center are mutually spaced by twice the distance between the openings in the distributor chamber.

Above and below the center where the distance between two valve openings is three times the distance between openings in the distributor chamber, the distributor valve should have n/2 valve openings if n represents the number of openings in the vacuum distribution chamber.

The vacuum distributor chamber may be mounted on the drop box, and the distributor slide valve on the bearing for the drop box whichis mounted on the loom.

In this manner, the displacement of the distributor valve relative to the openings in the distributor chamber, which is essential for effective control purposes, is effected automatically so that there is no need for any ancillary driving mechanism. The same advantage is secured, of course, if the arrangement is reversed and the distributor valve is mounted on the drop box, and the distributor chamber on the loom-mounted bearing for the drop box, the former arrangement, however, being preferred as it is the simpler one of the two constructions.

In the drawings accompanying this specification and forming part thereof, a preferred embodiment of the invention is illustrated diagrammatically by way of ex ample, and without any limitative intent.

In the drawings:

FIG. 1 illustrates schematically the drop box of a shuttle changing loom as seen from the side opposite to the operators station;

FIG. 2 is a similar schematic side view of the same drop box, viewed, however, from the operators station;

FIG. 3 is a longitudinal section on an enlarged scale, of the vacuum distributor chamber and distributor valve associated with the drop box of FIGS. 1 and 2, and

FIG. 4 shows, on a still further enlarged scale, a section taken along line IV-IV in FIG. 3.

Referring to the drawings wherein like elements are denoted by identical reference numerals, the drop box 1 which is disposed on the side of the lay (not shown in the drawings) comprises six shuttle compartments 2 2 2 2 2 and 2 The drop box 1 is mounted on a shaft 3 which is disposed for vertical displacement in a bearing 15 which is mounted on the loom (not shown in the drawing). By suitable control of the stroke of the shaft 3, and thus, the vertical displacement of the drop box 1, any one of the shuttle compartments 2 2 can be placed in the plane 4 of the lay. Picking is effected by causing a picking means (not shown in the drawing) to hit the shuttle in that compartment which is disposed in the plane 4 of the lay, and to throw the same through the shed into the box provided on the other side of the lay, the surface of the lay serving as the race.

As seen particularly in FIG. 1, the drawings illustrate the position in which the shuttle compartment 2 is situated in the plane 4 of the lay. The shuttle originally contained in the compartment 2 has been ejected from the compartment and is now located in the shed or in the box on the other side of the lay. The remaining shuttles 5 have remained in their compartments and are inactive. The wefts 6 deriving from these remaining, inactive shuttles 5 extend between the selvedge 7 and the exit for the weft on the respective inactive shuttle 5.

The pneumatic suction device with which the loom is equipped, comprises essentially a distribution chamber 8 mounted on the drop box 1, a suction manifold leading to the suction pump (not shown in the drawing and suction conduits 10 which lead from the distributor chamber 8 to the suction ports 11. The suction ports 11 are arranged in the side wall of the drop box 1 facing the operators station and in the vicinitcy of the openings facing the lay, of the shuttle compartments 2 2 and this in such a manner that shuttle compartments 2 2 2 and 2 are provided with two suction ports 11an upper port and a lower port-for each compartment, while the uppermost shuttle compartment 2 has only a lower suction port, and the lowermost shuttle compartment 2 has only an upper suction port.

Under the influence of suction, the wefts 6 deriving from shuttles 5 are pulled toward the ports 11 and thus, held tight over the entire distance between selvedge 7 and the weft exit of every shuttle 5; manifestly, this arrangement prevents the wefts 6 deriving from the inactive shuttles 5 from becoming entangled and from being carried along by the shuttle moving across the lay.

It is apparent from the drawing, and particularly from FIG. 1, that in all compartments containing an inactive shuttle, i.e. in compartments 2 2 2 2 and 2 only one of the suction ports 11 is effective in holding by suc tion, the weft 6 passing across such port, while the other one of the pair of ports 11 provided in each compartment is disposed remote from the path of the weft 6 and hence, is not effective in holding this weft; when it comes to the compartment, 2 the shuttle of which has been ejected from the compartment to proceed in the plane 4 of the lay, both suction ports 11 may be inactivated as neither is called upon to act on any weft 6. In accordance with the invention, those ports which are not needed for holding any weft 6, are shut off from the source of vacuum whereby the overall suction output, and therefore also the cost of the installation and operation of the suction system, are very materially reduced. The selective shut-off of all those suction ports which at any given point of operation of the shuttle changing device, are not needed for weft holding purposes, is effected, in accordance with the present invention, by a control organ which will now be described.

According to the preferred embodiment of the invention illustrated in the drawing, this control organ is provided in the form of a flat distributing slide valve 12 which is arranged in the distributor chamber 8, for sliding displacement along a series of apertures 13 13 13 13 13 13 13 13 13 and 13 which open into the suction conduits 10, and which are spaced from one another by one and the same distance. The distributing slide valve 12 is provided with a series of openings 14 14 14 14 14 14 14", 14 14 and 14 which are also mutually spaced, the distance between the openings 14 14 varying, however, in the following manner. The openings 14 and 14 are spaced by a distance which equals three times the spacing between adjacent openings of the series 13 13 of the distributor chamber 8; for adjacent ones of the remaining openings 14 14 and 14 14 the spacing is always twice the distance between adjacent openings of the 13 13 series.

The distributing slide valve 12 is mounted on the bearing 15 of the drop box 1 on the loom. The distributing slide valve 12, therefore, does not partake of the color change strokes of the drop box 1. Dependent on the position of the drop box 1 relative to the plane 4 of the lay, i.e. dependent on which of thte shuttle compartments 2 2 happens to be disposed in the plane of the lay, the distributing slide valve 12 assumes a predetermined position relative to the series of openings 13: 13 on the distributor chamber 8, which causes quite some of these openings 13 13 to be covered up. Only those openings 13 13 are kept open by the valve openings 14 14 which by suction conduits 10 are connected with those suction ports 11 which are absolutely required to be operational, i.e. which are needed for holding wefts 6 by the force of suction. Covered up, therefore, are those among openings 13 13 which are correlated with (a) both the suction ports 11 of the shuttle compartment which is disposed in the plane of the lay, (b) the lower suction ports of the shuttle compartments disposed below the plane of the lay, and (c) the upper suction ports of the shuttle compartments disposed above the plane of the lay.

FIG. 3 shows a position of the distributing slide valve corresponding to the position of the drop box as illustrated in FIGS. 1 and 2. As the drop box 1 rises or descends, the distributor chamber 8 including the series of openings 13 13 rises and descends correspondingly, and the distributing slide valve assumes an ever varying position relative to the series of openings 13 13 this position always corresponds, however, to the control scheme described above.

The distributing slide valve 12 is guided, as illustrated in FIG. 4, in the dovetailed groove of a rail 16. Guide and packing members 17 are mounted at the top and bottom points of exit of the slide valve from the distributor chamber 8. The upper packing member can be disposed with if the chamber 8 is sufliciently extended upwardly.

The flat side valve 12 shown in the drawings, may be replaced by a circular slide valve with valve openings which like a rotary piston, is arranged in a cylinder, the rotary piston being activated from the drive shaft effecting the upward and downward displacement of the drop box and the cylinder assuming the function of the vacuum distributor chamber.

I wish it to be understood that I do not desire to be limited to the exact details of construction, design and operation shown and described, as modifications within the scope of the claims following below, and involving no departure from the spirit of the invention nor any sacrifice of the advantage thereof, may occur to persons skilled in the art.

Iclaim:

1. In a loom including a drop box, a pneumatic weft holding device, compartments in said drop box which open in the direction of the lay, suction ports in the side wall of said drop box which are adjacent said compartment openings, a vacuum distributor chamber for said pneumatic weft holding device, said vacuum distributor chamber having a plurality of equally spaced apart openings which connect to a plurality of corresponding suction conduits leading from said vacuum distributor chamber to said suction ports in said drop box, the improvement which, comprises a distributing slide valve arranged in said vacuum distributor chamber for displacement along said openings in said distributor chamber, said slide valve having openings which are spaced from one another at the center of the valve by three times the distance between adjacent openings in the distributor chamber and above and below the center of the valve by twice the distance between adjacent openings in the distributor chamber to adapt the slide valve to selectively close some of said openings in said vacuum distributor chamber in response to the prevailing position of the drop box relative to the lay.

2. The combination as claimed in claim 1, wherein said vacuum distributor chamber is mounted on said drop box and said distributing slide valve is mounted by bearing means on the loom, said bearing means also mounting said drop box on the loom.

References Cited UNITED STATES PATENTS 2,762,399 9/1956 Moseley et a1 139-170.3 2,842,164 7/1958 Head 139-170.3 3,186,444 6/1965 Schaifer 139-194 X 3,238,976 3/1966 Rainer 139170.3

OTHER REFERENCES Samar-Pneumatic Weft Separator, 1 sheet received June 3, 1964.

MERVIN STEIN, Primary Examiner.

15 I. KEECHI, Assistant Examiner.

Claims (1)

1. IN A LOOM INCLUDING A DROP BOX, A PNEUMATIC WEFT HOLDING DEVICE, COMPARTMENTS IN SAID DROP BOX WHICH OPEN IN THE DIRECTION OF THE LAY, SUCTION PORTS IN THE SIDE WALL OF SAID DROP BOX WHICH ARE ADJACENT SAID COMPARTMENT OPENINGS, A VACUUM DISTRIBUTOR CHAMBER FOR SAID PNEUMATIC WEFT HOLDING DEVICE, SAID VACUUM DISTRIBUTOR CHAMBER HAVING A PLURALITY OF EQUALLY SPACED APART OPENINGS WHICH CONNECT TO A PLURALITY OF CORRESPONDING SUCTION CONDUITS LEADING FROM SAID VACUUM DISTRIBUTOR CHAMBER TO SAID SUCTION PORTS IN SAID DROP BOX, THE IMPROVEMENT WHICH COMPRISES A DISTRIBUTING SLIDE VALVE ARRANGED IN SAID VACUUM DISTRIBUTOR CHAMBER FOR DISPLACEMENT ALONG SAID OPENINGS IN SAID DISTRIBUTOR CHAMBER, SAID SLIDE VALVE HAVING OPENINGS WHICH ARE SPACED FROM ONE ANOTHER AT THE CENTER OF THE VALVE BY THREE TIMES THE DISTANCE BETWEEN ADJACENT OPENINGS IN THE DISTRIBUTOR CHAMBER AND ABOVE AND BELOW THE CENTER OF THE VALVE BY TWICE THE DISTANCE BETWEEN ADJACENT OPENINGS IN THE DISTRIBUTOR CHAMBER TO ADAPT THE SLIDE VALVE TO SELECTIVELY CLOSE SOME OF SAID OPENINGS IN SAID VACUUM DISTRIBUTOR CHAMBER IN RESPONSE TO THE PREVAILING POSITION OF THE DROP BOX RELATIVE TO THE LAY.

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