US2972086A - Removal of static electricity in fibers, textile materials, and other materials capable of being charged with static electricity - Google Patents

Description

Feb. 14, 1961 A. NAu-TouRoN 2,972,036 REMOVAL OF STA'I'IC ELECTRICITY IN FIBERS, TEXTILE MATERIALS, AND OTHER MATERIALS CAPABLE OF BEING CHARGED WITH STATIC ELECTRICITY 3 Sheets-Sheet 2 Filed July 12, 1955 Feb. 14, 1961 A U-TQURQN 2,972,086

REMOVAL OF' STATIC CTRICITY IN FIBERS, TEXTILE MATERIALS, AND O MATERIALS CAPABLE OF BEING CHARGED WITH STATIC ELECTRICITY Filed July 12,' 1955 3 Sheets-Sheet 3 United States Patent O REMOVAL OF STATIC ELECTRICITY IN FIBERS,

TEXTILE MATERIALS, AND OTHER MATE- RIALS CAPABLE OF BEING CHARGED WITH STATIC ELECTRICITY Albert Nau-Touron, Paris, France, assigner to Centre Technique Industriel dit Institut Textile de France, Paris, France Filed July 12, 1955, Ser. No. 521,588 Claims priority, application France July 28, 1954 6 Claims. (Cl. 317-2) This invention relates to the elimination of static electricity in materials, more particularly in fibers or textile structures which tend to become charged.

It is known that the individual or combined action of many factors can, by acting upon insulating materials possessing a certain dielectric constant, create a charge thereon. These factors are very numerous and include solid or even gaseous friction or internal stresses within the insulating materials.

This charging action of the above-mentioned factors will generally occur both in the textile industry and in the industrial treatment of cellulose products such as, for example, paper, plastic materials, or even powders, etc.

It is an object of the present invention to provide means for eliminating these parasitic influences in the case of textiles. But it should be understood that the present invention is equally applicable to all the abovementioned industries, and more particularly to any industry dealing with a material which may become electrically charged.

Efforts have hitherto been made to eliminate the abovementioned inconveniences by the use of certain processes of electric neutralization which are based on calorific and hygroscopic conditioning of the workshop atmosphere. Unfortunately, such installations are deterirnental to the health, of the personnel and are unduly bulky and Very costly to install.

According to the invention a stream of gas previously exposed to a radio-active substance is projected on to the material charged with static electricity. It has been found that a jet of gas conditioned in this manner will cause complete and practically instantaneous disappearance of the parasitic electric charges on the material with whichit comes into contact.

The present description and the following full description will initially refer to schematic embodiments of the application of the invention, then proceed to a description of forms of apparatus incorporating further improvements, and will finally relate to forms of apparatus particularly applicable to machines which stretch textile threads and machines which spin the latter.

In the accompanying drawings:

Figure 1 is a schematic View illustrating one Way in which a gas jet according to the invention may be produced;

Figure 2 is a similar view of a rnodilication in which the gas jet is directed from below;

Figure 3 shows a particular construction of the radioactive surface;

Figure 4 shows a particular form of the inlet and spray nozzle for the gas jet;

Figure 5 is a section showing the end of a gas spray nozzle;

Figure 6 is a transverse sectional View of a form of active surface is increased;

which the delivered gas is produced by mixing two constituents;

Figure 12 shows another similar apparatus having a different nozzle;

Figure 13 shows a form of apparatus according to the invention in which the nozzle is detachable;

Figure 14 shows an apparatus similar to that of Figure 13 provided with means for producing the gas used by mixing two constituents;

Figure 15 Shows a form of apparatus in which the amount of radio-active material in contact with the flow of gas can be varied;

Figure 16 is a modification of Figure 15;

Figure 17 represents an apparatus according to the invention installed in a textile machine to effect removal of electrtic charges;

Figures 17a and 17h are sections, respectively on lines XVIIa-XVIla and XVIIb-XVHb, of Figure 17;

Figure 18 is a sectional elevation of a form of apparatus concerned in particular with, but not limited to, spinning and twisting machines and by which the thread formed or being formed in these machines is de-electrilied during its passage through the interior of this deelectrifying apparatus;

Figure 19 is a side elevation of the apparatus shown in Figure 18;

Figure 20 is a plan view of the apparatus of Figure 18 in one position; and

Figure 21 is a similar view of the apparatus of Figure 20 in a different position.

The process according to the invention consists in directing a gas jet on to a radioactive layer and utilizing this jet after its passage over the radio-active layer. The gas jet has an increased activating power, due both to the particular ionizing a rays originating from the ldecay of the natural or artificial radio-active substances employed, and to the less strongly ionizing rays.

As shown schematically in Figure l, a bed plate 1 is coated on one of its Hat sides with a layer 2 of natural or artiiicial radio-active elements. A stream of gas is blown at a certain angle ce relative to the coated sur face. The gas stream is applied by means of a rigid or flexible passage 3 and, as indicated at 5, forms with the coated surface a certain angle The action of the reflected jet 5 on the parasitic electric charges Varies according to the initial composition, speed, temperature, and like characteristics of the ilow of gas arriving at 4.

While Figure l shows an embodiment in which the jet is directed upwards, Figure 2 shows that the jet may also be directed downwards. Moreover the coated surface may be at an angle qb with the horizontal.

It should be noted that the case in which a is zero is not excluded. In this case all of the surface 2 is exposed to the gas stream which moves in the direction of the arrow 8.

The end 6 of the channel nozzle 3 may be cut ofi at an angle as seen in Figures 1, 2 and 3, or the end of the nozzle may be constructed as shown in Figure 4, in which the square cross section of the nozzle includes a rectilinear part parallel to the surface 2. and twO volutes 9 which serve to produce a whirling effect on the applied jet of gas.

Similarlyr the radio-active layer 2 may, as shown in Figure 3, be formed with corrugations 7 which prolong the contact between the gas stream and the radio-active material.

The end of the'nozzle may, as shown -in Figure 5, have a conical portion 12 which contains a pointed cone 10 ending in a point or needle 11. With this arrangement (Figure a laminar discharge is obtained without turbulence and flicker of the gas jet.' Moreover, advantage may be taken of the electrostaticV effect of the point 11. The section of the passage 13 of the gas ow decreases towards the point, thus causing an increase in the speed of the gas over the layer 2.

Figures 6` and 7 represent a very similar nozzle, in which, however, the gas ejection orice is spread out laterally over the radio-active surface. The mouth of the nozzle is thus shaped like a small tongue. This arrangement may also beprovided with Va cone body similar to that of Figure '5, but having a knife-edge and extending along the mouth 14. As shown in Figure 6 the bed plate 1 has a special shape producing desirable convection eiects and reducing turbulence in the ow.

The components described above as well as those vdescribed below may be made either of conductive or of insulating materials. K

The radio-active layer 2 may be applied evenly over the bed plate 1, or its thickness may increase in the direction of the gas flow.

Figures 8 and 9 show arrangements in which a certain quantity of radio-active materialcovers the inner wall surfaces of the end of the nozzle 3. If desired, a certain number of lateral apertures 16 maybe provided at the end of the nozzle. According to Figure 9, the end of lthe nozzle 3 has a cap 17 formed with perforations 18,

the profile of which is selected to produce convection eiects and increase the kinetic energy. Radio-active material is distributed on the rear randfront walls 19 and 20 respectively of the cap 17.

It is generally preferable that the layer 2 be very thin to prevent absorption of the mass of these radio-active elements. The bed plate 1 in the region of the coating may be ofV any shape, more particularly flat, concave, convex, and the like.

The angle must be chosen in such manner as to remain, under the law of mechanics of uids, between the critical values at which the fluid becomes detached from the coating 2.

If it is desired for the gas stream to be humiditied, this can be done by the well-known methods of bubbling into water or by a prolonged passage of the gas jet over the surface of an expanse of liquid. By reason of a certain probable recombination eiect the air bubbled in the water loses a large part of its conductibility in the presence of radium'and the second method may be preferred to that of bubbling. Y

Generally the gas stream or jet may contain in suspension carefully and deliberately chosen dust and other small particles.

The gas stream may be previously subjected to the actionY of phosphorous anhydride or an aqueous solution of deliquescent salt to increase the ionizing power'. A certain mixing of the gas ow with ozone or oxygen may be provided if desired and in this case a neutralizing sweeping or wiping action with a brush or a cloth, having an effect upon the matter to be de-electried, may be effected by any suitable vmeans and in any Yrelevant plane or direction. K K K KY K' Moreover, when the positive or'negative polarity of the material to be treated is known, one may, by means of a magnetic eld,'deflect according to the polarity the a'. or ,6 rays arising fromKthe decay of the radio-active substances. K K K Y u .K Y

In this manner, a discriminating selection between a and `rays is obtained.`

Figure 10 shows one embodiment of the apparatus using the above process. A certain number of elements already referred to have been represented by the same reference numerals. The bed plate 1 is supported by an arm 21 hinged at 23 to a xed base 22. A collar 24 in which the nozzle 3 slides is hinged at 25 to the bed plate carrying arm 21, a set screw 26 enables the nozzle to be clamped in the collar 24. Y

The hinge 23 enables the direction of the radio-active jet to be adjusted as desired, While the hinge 25 cooperating with Vthe telescopic mounting of the nozzle 3 enables the distance 25 between the nozzle and the radio-active surface 2 to be varied.

Figure .11 shows a modification applicable to the apparatus according to Figure 10, in which the gas flow comprises a mixture of two gases produced by an injector arrangement. The gas under pressure arrives at 26', the conveyed gas arrives at 27 under reduced pressure in the chamber 23. Two valves 29 andv 30 enable the relative supply of the two gases to be controlled.

Finally, as in the case of Figure 10, the supply of gas reaching the nozzle 3 is regulated by the valve 15, while that of the conveyed gas is regulated by the valve 30.

Figure 12 shows a nozzle similar to that of Figure 8 but mounted in a collar as in the apparatus shown in Figures 10 and 11.

In Figure 13 the nozzle 3 and the radio-active layer 2 are arranged in a half-closed chamber unit 31 having openings such as indicated at 72 (Figures 13, 14, 15, 16) preferably in the proximity of the vradio-active layer 2. The gas jet is directed into detachable spray nozzle 32 having a tubular bore 33. K

Figure 14 shows Kan arrangement similar to that of Figure 13, in which the angle a is reduced to zero. The nozzle of the conduit 3 has a mouth 3K4 of a width equal `to that of the layer 2, and a gas mixing arrangement similar to that of Figure l1 is shown in the apparatus.

In Figure l5 the flat bed plate is replaced by aY sector 35 covered by an intervening curved bed plate 1. The inclination of the sector 35 may be externally controlled by means of a shaft 36, to which the sector 35 is rigidly attached. and which can turn with respect to the chamber unit 31. A cover 37, which is easily removed, permits access to the segment 35. This arrangement has the advantage that the quantity of the radio-active matter affected by the gas flow from the nozzle mouth 34 can be very conveniently varied.

Figure 16 shows a modification of the construction of Figure 15 in which the two constituents of a gaseous 'mixture are introduced at 3 and 33. The second gas,

the supply of which is regulated by a valve 39, arrives in the direction 4th and the linal mixture is produced at 41. Y

Figure 17 shows how an apparatus according to the invention may be used to eliminate static electric charges on libers which are induced by stretching in the course of their treatment in'various types of textile machines concerned with natural, artificial or synthetic textiles. Consequently the illustrated example of the application to a spinning machine does not limit the invention to this type of machine.

A sliver 42 passes between the grooved rollers 43 and 44, in front of a thread-guide or pigtaiL and it leaves the rollers 43 as a completelyor partially formed thread 45. The zone in which the apparatus according to the invention will be arranged to work is at 46, for itis in this zone that the final rate of stretching reaches a maximum value. This produces internal rubbing of liber against liber and against metal and also the sliver is already partially electrified by reason of previous rolling operations. It should be noted that there is also an elec- ,trifying zone beyond the Contact point 47 of the rollers the width of the thread, is supported by a frame 50 by means of an angle bracket 49 with the interposition of a frontal rail 51. A tubular rod 52 having a mouth piece 53 at its upper end, is joined to the base of the blast pipe 48. Suicient tightness is assured by the contact of the rod 52 and the blast pipe 48, due to the elasticity of the sides 54 and of the latter.

All the previously mentioned measures for the formation of the gas jet may be used in this particular case.

An alternating frontal displacement synchronized with and equal .to that of the sliver-guide bar, or of the ribbonguide bar or other similar mechanism in other textile machines, may be provided to permit a reduction in width of the base ofthe blast pipe and its nozzle.

It is obvious that when a certain number `of these apparatus units are disposed laterally and the above-described alternating movement is used, one may treat not only slivers or threads but also structures composed of bers or tissues of a certain Width.

An apparatus will now be described which is rather different from the preceding example, which is especially important for spinning and twisting machines but is not limited in use |to such machines. In the case of a spinning machine this apparatus (Figure 18) operates in a different zone from that of the preceding case, viz; beyond the line of contact 47 with the grooved rollers 43.

The thread 45 which has already been completely or partially formed by ytorsion passes through the interior of the apparatus.

Another important feature consists in the fact that the apparatus works at a reduced pressure and can be put to other supplementary purposes, as will be described below.

In Figure 18 the reference numeral 56 designates the thread guide or pigtaiL the apparatus itself being placed in front of the thread guide 56. A front suction tube 57 acts on all the individual apparatus units arranged on the individual spindles of the machine.

Clips 58, suitably distributed along the tube 57 secure the tube on the machine frame 50 or preferably on the front rail 51, while leaving it free to turn about its axis and move, as in the preceding apparatus and for the same purpose, forwards and alternatingly in the direction of the arrows 59 (Figure 20). To the right of each thread 45 a suction-operated blast pipe 60 of, for example, rectangular section, constitutes a delivery tube joined to the tube 57. The gas jet is represented by the arrow and the reference numeral 55, taking into consideration the fact that the kinetic energy of the gas is poduced in this case by a reduced pressure in the tube 5 In the vicinity of the outer end 61 of the blast pipe, the general arrangement described above as adopted for the bed plate and its coating of radio-active material is again provided. At the other end of the injector nozzle a lateral opening 62 permits the easy passage of the strand of thread. A sliding obturator 63 can be locked 'in position by means of a set screw 65. In the working position (Figure 21), the closing device 63 is moved in the direction of the arrow 64 to cover the lateral part of the opening 62 and to leave only two circular orifices through which the thread 45 passes.

As in the previously described embodiments, .the radioactive jet 55 acts upon the thread 45 as the latter moves in the direction of the arrow 66, and eliminates from it instantaneously all parasitic electrostatic charges.

An orifice 70 in the suction pipe 57 in the vicinity of the opening 62, constitutes a preliminary suction point. This is important when the thread 45 breaks and a tieing up operation is required. The strand of bers 67, then loose and free, is drawn in the direction of the arrow 68 by the junction 69 of the suction tube 57 with the injector nozzle 60. The orice 70 helps, by means of a slight suction, the guiding and automatic introduction of the loose strand 67 in the direction of the arrow 68 and across the opening 62, due to the provision of the orifice 70, extending at an appropriate angle to the right of each suction-operated blast and neutralizing tube 60.

The opening 62 may be replaced at the desired inclination by two opposed circular orifices joined on one lateral side of the tube by a saw cut.

Preferably grounded, the various arrangements described above by way of example assure a soft and supplementary continuous cleaning action on the ionizing exterior surface of the radio-active layer 2. This prevents dust or iine suspensions of textile in the air from becoming deposited on the radio-active surface and thus interfering with, or even destroying, the neutralizing action of the said surface.

When the machine is stopped to carry out lifting," removal of the full bobbins and the insertion of the empty tubes or bobbins on the spindles may, if required, be simplified by the removal of the front base portion of the blast pipes 60. This may be done by simply turning the tube 57 upwardly in the collars 58 by a sufficient angle. Before the machine is put into operation again, the blast pipes are restored to the working position, by simple inverse rotation of the tube 57.

It should be noted that in this application to a spinning machine, the reduced-pressure flow of gas in the tube 57 of the last-described arrangement may be recovered, wholly or partly, as a flow under pressure for feeding the tubular rod 52 of the preceding arrangement. Moreover, this last arrangement could, due to its de-electrifying action, form a useful addition to known suction systems for threads by simply adding a neutralizing blast tube, while the number of components and equipment units may be retained.

Since the invention has been described above only by way of several illustrative embodiments, the apparatus described may be altered or adapted to particular conditions without departing from the scope of the invention. In particular the specific example of applying it to the elimination of charges of static electricity on textiles is entirely arbitrary and any applications in various spheres based on the same principle are equally covered by the lnvention.

The present invention provides arrangements by means of which a particularly rapid electric neutralizing action can be obtained. The length of time required for deelectriiication is reduced practically to its minimum, whichns. one advantage of substantial importance over the existing art. Moreover, in the apparatus according to the invention, the action is adjustable in intensity and extent.

I claim:

1. An apparatus for removing parasitic static electricity .from dielectric materials which comprises means defining an exposed radio-active surface, a support for said surface, a nozzle for connection to a source of gas under a pressure greater than atmospheric, said nozzle directing a stream of said gas into intimate contact with said exposed surface, means for directing the gas stream after impingement upon said radio-active surface into engagement with said dielectric materials, a hinge connection between said support and said nozzle, and an inclinable collar in which said nozzle is telescopically mounted for adjustment of the distance between the end of the nozzle and said surface.

2. An apparatus for removing parasitic static electricity from dielectric materials which comprises means defining an exposed radio-active surface, means for directing a mixture of gases into intimate contact with said exposed surface, said directing means including means for connection to a source of one of said gases under a pressure greater than atmospheric and for supplying said one of the gases to form said mixture of gases, an injector arrangement for aspiring the other of said gases, and means for directing the gas stream after impingement upon said radio-active surface into engagement with said dielectric materials.

3. An apparatus for removing parasitic static electricity from Vdielectric materials which comprises means defining an exposed-radio-active surface, a support for said surface, a nozzle for connection to a source of gas Yunder a pressure greater than atmospheric, said nozzle directing a stream of gas into intimate contact with said exposed surface, means for directing the gas stream after `irnpingement upon said radio-active surface into engagement with said dielectric materials, a hinge connection between said support and said nozzle and an inclinable ,collar in which said nozzle is telescopically mounted for adjustment of the distance between the end of the nozrzle and said surface, a sector pivoted under the nozzle :for directing the gas stream with an angle of incidence 'of the gas stream on the radio-active surface adjustable j between 0 and 90, and ,said directing means compris- .Y ing a detachable blast pipe which discharges and directs the radio-active gas stream.

4. An apparatus for removing parasitic static electricity from dielectric materials which comprises means defining an exposed radio-active surface, a support for said surface, a nozzle for connection to a source of gas under a pressure greater than atmospheric, said nozzle directing a stream of gas into intimate contact with said exposed surface, means for directing the gas stream after impingement upon said radio-active surface into engagement with said dielectric materials, a hinge connection between said support and said nozzle and an inclinable collar in which said nozzle is telescopically mounted for adjustment of the distance between the end of the nozzle and said surface, and means for providing a reduced pressure at a point beyond the radio-active substance.

5. An apparatus for removing parasitic static electricity from dielectric materials in a spinning machine having a suction chamber comprising communicating suction openings for`receiving thread elements, meanssfor defining a radio-active surface, means for connection to a source of gas under a pressure greater than atmospheric, said means directing a stream of said gas into lintimate contact with^said radio-active surface, and means for directing the gas stream after impingement upon said radio-active surface into engagement with said dielectric material, said suction chamber comprising an aperture spaced` from said suction openings for applying a limited forcepupon said thread elements whereby the same are guided into said suction openings.

6. In a multi-spindle textile machine, a plurality of devices for removing parasitic static electricity from the threads being spun, each device comprising means defining anV exposed radio-active surface, means for con nection to a source of gas under a pressure greater than atmospheric, said means directing a stream of gas into intimate contact with said exposed surface, and means for directing the gas stream after impingement upon said radio-active surface into engagement with said threads, said devices being connected to a common suction conduit on one side of said machine, and said devices being connected to undergo an alternating frontal movement relatively to said machine.

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