US2132708A - Method for treating materials and electrical treating apparatus, especially for sterilization - Google Patents

Description

Oct. 11, 1938. F 5 $M|TH 2,132,708

METHOD FOR TREATING MATERIALS AND ELECTRICAL TREATING APPARATUS, ESPECIALLY FOR STERILIZATION Filed Oct. 8, 1934 2 Sheets-Sheet l INVENTOR. Han 42 //v 5. J/Y/r/v ATTORNEYS Oct. 11, 1938. s $M|TH 2,132,708

METHOD FOR TREATING MATERIALS AND ELECTRICAL TREATING APPARATUS, ESPECIALLY FOR STERILIZATION Filed Oct. 1934 2 Sheets-Sheet 2 INVENTOR. fkAA/Ku/r J 7 ATTORNEYS I I A z 4; mv oQum 'atented Oct. 11, 1938 2,132,708

UNITED STATES PATENT GFFICE METHOD FOR TREATING MATERIALS AND ELECTRICAL TREATING APPARATUS, ES- PECIALLY FOR. STERILIZATION Franklin S. Smith, New, Haven, Conn.

Application October 8, 1934, Serial No. 747,442

7 V 25 Claims. (01. 21-54) This invention relates to apparatus which is or standards II and I2 in the upper ends of articularly adapted for electrically sterilizing roducts, such as food products or the like.

One of the objects of this invention is to prowhich, in suitable bearings, are rotatably supported drums f3 and I4, respectively, the latter having extending thereover a conveyor belt 15 ,de a practical and inexpensive-apparatus for made of a suitable material, preferably non-con- 5 se among other things in destroying insect life, ductive, such as cotton, or the like. The upper ich as eggs, pupae, larvae, and the like, conside of the belt I5 functions to carry and move lined in products such as food products, illusthe product to be sterilized, illustratively packatively cereals, flour, and the like. Another obaged food products IS, in a direction from the rot is to provide an apparatus of the above-menright to the left, through a treatment zone to oned character in which insulation problems be hereinafter more clearly described. Any other 1d the like are overcome in a dependable and suitable means may be provided for feeding the [expensive way. Another object is to provide an product I6 to one end of the conveyor and for ectrical sterilizing apparatus in which the elecremoving the treated product from the appaical discharge is dependably controlled and, ratus at the other end. loreover, by way of means that is compact and The conveyor I5 may be driven in any suitable lEXPEI'lSiVG and dependable in action. Another manner, illustratively by a motor l1, preferably iject is to provide apparatus of the above-menmounted in the base of the machine, suitably oned character in which the conditions under geared or connected to the drum I3, as by the hich certain discharge electrodes operate are bevel gears I8, by which a vertical shaft I9, supreatly improved and in which also superior elecported in suitable bearings carried by the standode or discharge action is achieved. Other obard II, is driven, suitable gearing such as a worm :cts will be in part obvious or in part pointed 20 and a worm wheel 2I connected to the shaft it hereinafter. I9 and the drum I3, respectively, completing the The invention accordingly consists in the feadrive of the drum I3 and hence of the conveyor I5. was of construction, combinations of elements, The upper side of the belt l5 supported against 1d arrangements of parts and in. the several sagging by a table-like structure which, illustraeps and relation and order of each of the same tively, may comprise a plate-like member 22 exone or more of the others, all as will be illustending from the drum I3 to the drum l4 and atively described herein, and the scope of the underneath the upper side of the belt I5; plate )plication of which will be indicated in the folmember 22 is of insulating material, such as wing claims. flaminated bakelite. It may be supported in In the accompanying drawings in which is position in any suitable manner, illustratively by IOWll one of the various possible embodiments two side beams 23 and 24, also made of solid F the electrical and mechanical features of my dielectric material and supported at their ends .vention, in any suitable manner, illustratively by the pairs Figure 1 is a front elevation of a complete apof standards II-I2.

iratus, certain parts being diagrammaticallyin- Intermediate of the drums I3-I4 I provide a .cated; suitable treatment zone, the latter being achieved Figure 2 is a plan view as seen along the line by certain coacting parts, certain of which are Q4 of Figure underneath the product-carrying side of the belt Figure 3 is a view on an enlarged scale, partly and certain of which are above, and for convenelevation and partly in vertical section, of an ience the latter may be considered first. Acectrode structure and driving means therefor cordingly, I position, above the belt I5 an elecid which'forms part of the apparatus of Figure trode means generally indicated at 25 which in and cludes the rotatable electrode proper 25 provided Figure 4 is a view, partially in plan and partialwith a suitable number of downwardly directed in horizontal section, of the apparatus of Figelectrode elements or discharge points 26, preferre 3, as seen along the line 4-4 of Figure 3. ably arranged in a circle in the rotatable carrier Similar reference characters refer to similar portion of the electrode 25 and driven in a manlItS throughout the several views in 'the drawner about to be described, and with their lower gs. ends in a plane spaced upwardly from and pref- Referring now to the drawings and more parerably parallel to the plane of the product-carrycularly to Figure 1, I have there shown a main ing side of the belt I5. The products are moved ame II) having, at its ends, pairs'of uprights by the belt through the space between these two planes. The electrode elements 23 are maintained at a relatively high potential, a potential of the order of 150,000 volts, and preferably an alternating one, preferably of a relatively high frequency, such as, for example, 640 cycles per second.

This energizing potential may be derived from any appropriate source and illustratively I may provide an alternator 21 of the appropriate frequency and of low voltage connected to the low voltage winding 28 of a step-up transformer 28-129 whose high voltage winding 23, yielding a voltage on the order of 150,000 volts, has its one side grounded, preferably to the frame I, as at 30, by conductor 3|, and has .its other side or terminal connected, as by conductor 32, to the electrode which, with it's electrode elements 26, is thus maintained at this high potential relative to the base frame iii, to achieve certain electrical actions, certain of which are described later hereinafter. p

- The high voltage electrode structure 25 is provided with a shaft-like stud 33 rigidly mounted in a bracket 34 which in turn is secured to an insulating support 35, illustratively in the form of a beam or beams of solid dielectric material and in turn mounted for movement vertically and hence toward oraway from the conveyor l5. Any suitable means may be provided for thus mounting the insulating frame 35 and illustratively its ends may be provided with suitable devices 36 and 37 which may be adjustably positioned along upward extensions of the main frame. l0, illustratively indicated at H and I2, respectively. The insulating beam structure 35 positioned to hold its bracket 34, positions the rotating electrode elements 26 relatively centrally over and with respect to the belt i5, and is suitably shaped and dimensioned adequately to insulate the high voltage electrode 25 from the metal parts of the supporting frame.

As above indicated the electrode 25 is rotated; for reasons and advantages, certain of which are later pointed out, I achieve this rotation or movement of the electrode 25 by means of a fluid motor operating, in coaction with other parts, under a non-conductive fluid under pressure, illustratively suitablydried air under a suitable pressure. v a

The fluid motor may, as in the form illustratively shown in Figures 3 and 4, be an integral part of the electrode 25. Reference may first be made to Figure 3, in which the stud 33, nonrotatably secured'to and depending from the bracket 34 (of Figure l) rotatably supports a twopart housing 40-41; housing 40 has a hub-like portion 40 suitably counterbored to have tightly fitted therein the outer, race 42 of a combined thrust and radial anti-friction bearing 42 whose inner race 42 is tightly fitted or otherwise secured to the stud 33.

The housing 40, otherwise generally disk-like in shape, is provided with a downwardly extending peripheral cylindrical portion 40b, with which the outer upper face of the disk-like housing I member 4! mates, the two members 404l thereby enclosing an appropriate space therein andtherebetween.

Housing member 4| also has a hub-like portion til suitably counterbored to tightly receive or have otherwise secured thereto the outer race 43 of a suitable combined radial and thrust antifriction bearing, generally indicated at 43, whose inner race 33' is tightly fitted or otherwise secured to the lower end of the stud 33. With the housing parts 30-4! secured together, as by screw: 44 (Figure 4) and assembled, after interposing therebetween certain parts about to be described the housing 40-4l is thus carried by the stud 31 for free rotation thereof aboutthe axis of the stud itself. r

The hub portion 40 of the upper housing member is provided with 'an aperture 30" through which the stud 33 emerges from the housing whereas the hub portion 4 I of the housing member 4| is closed by a wall portion ti adjaceni the upper face of which the stud 33 terminates Now the outer part of the housing member 4| is provided with an annular rib il through which extends a series of preferably equally spaced threaded holes 45 (see also Figure 4) but the axes of these holes are inclined to the general plane in which the housing 40M rotates sc that when the electrode elements 20, the latter being generally tubular (see Figure 3) and having their upper ends threaded, are threaded into the holes 45, the electrode elements 26 are inclined away from the direction in which they, with the housing 404l, rotate about the stud 33, the upper ends of the electrode elements 26 therefore being the leading ends and the lower ends thereof being the trailing ends.

When the electrode elements 26 are arranged about a single circle, the diameter of the latter is preferably somewhat lessthan the width of the conveyor belt l5 above mentioned in connection with Figure l.

Interposed between the housing members 40-4l (Figure 3) and non-rotatably secured to the stud 33 is a vane structure generally indicated at 46 in Figure 3, and preferably made of two parts 4! and 48, each substantially disk-like in shape. The disk part 48 is provided with a hub portion 48 secured to the stud 33 as by the taper pin 49. The coacting disk part 4'? is provided with a hub portion 4'! secured to the stud 33 as by the set screw 50. As better appears in Figure 3, the disk parts 41-48 are spaced apart and adequate clearances are provided between them and the respectively adjacent housing parts 40-4l. Extending between the thus, spaced disk parts 41 and 48 and preferably formed integrally with one of them, e. g. the part 48, is a plurality of vanes 48 shaped and positioned substantially as shown: see Figure 4. They extend in a generally radial direction but at their inner ends are curved as shown and terminate in a circle concentric with the axis of the stationary stud 33, forming a central or annular-like chamber 46 about the stud 33 (see Figure 4) closed at'its upper and lower sides (see Figure 3). by the inner portions of the disk parts 4148 and/or their hub portions fi -43 To this annular chamber 46 fluid under pressure is supplied preferably by passages or channels provided in the stud 33 itself. For this purpose, the stud 33 is tube-like throughout a substantial portion of its length, being provided with a passage 33 formed, for example, as by drilling axially of the stud 33 (in a vertical direction, as viewed in Figure'3) to a suflicient extent to carry the upper end of the channel 33 beyond the upper part of the rotatable housing member 40; at that-point a horizontal passage 33' is formed as by drilling and is then tapped or threaded to receive a nipple or piece of tubing Mwhieh is supplied with fluid under pressure in a manner hereinafter described. The extreme lower end of the passage 33 is closed or sealed, as ,by a threaded plug 53 u 3) and throut that portion of the stud 33 that is'exposed to the above-mentioned annular chamber 46, the walls of the stud 33 are provided with a suitable number of apertures 33*, whereby the fluid under pressure emerges from the channel (i3 (Figure 3) into the annular chamber 46 (Figures 3 and 4) and thusexpands and moves at a suitable velocity, under the guidance of the vanes 48* (Figure 4) in a generally. radial direction between the disk parts 41-46 of the stationary vane structure 46, from which the still expanding fluid emerges in a general radial direction to impinge upon blades 4|! carried by the rotatable housing The blades 40 (see'Figure 3) may be integrallyformed with one of the housing members, such planes of the disk-like horizontal wall portions 40-. In horizontal section they are shaped as is better shown in Figure 4, from which it will be seen that their inner ends terminate adjacent the periphery of the stationary vane structure 46, the blades 46 extending at suitable angles or curvatures to form therebetween horizontal passages 4|) closed at their outermost ends excepting for the passages 26 (Figure 3) through the electrode elements 26, through which the expanded fluid escapes. Accordingly, and illustratively, I provide as many blades 40 (see Figure 4) as there are threaded holes 45 and hence electrode elements 26, and with the shaping of the parts as above described and as is better shown in Figures 3 and 4, the housing 40--4I with its circular row of electrode elements 26, is rotated in clockwise direction, as viewed in Figure 4, at a suitable speed, illustratively 1200 R. P. M.

As is better seen from Figure 3, the passages 26 in the electrode elements 26 are nozzle-shaped, and this shape and the resultant action thereof on the finally discharged fluid, in conjunction with the inclination of the electrode elements 26 and hence of the nozzles (see Figures 3 and 4) act also to contribute toward the driving force or energy of rotation, thus supplementing the coactions and effects of the above-described stationary vanes and moving blades. But, as will be better seen when the electrical actions of the apparatus are considered, this nozzle action of the electrode elements 26 coacts also to achieve other results and advantages.

The fluid motor above described and thus embodied into the electrode means 25, is supplied with operating fluid that is preferably a dry gas under pressure, such as dried air under pressure. Accordingly, I provide a suitable air compressor 66 (Figure l) driven in any suitable manner, illu'stratively by the motor l1, through suitable gearing 6|. From the compressor 60 the compressed air passes through a separator 62 of any suitable construction and in that separator foreign matterand particularly moisture are removed from the air. Compressor and air conditioning apparatus may conveniently and preferably be positioned underneath the conveyor and carried bythe base frame ll! of the apparatus.

Extending upwardly from separator 62 to a point adjacent electrode means 25 is rigid conduit 63. Attached to the upper end of rigid conduit 63 and extending to nipple 52 upon electrode means 25 is flexible conduit 64. Nipple 52 is connected through passages 33"., 33 and 33' to fixed vane 46. A valve 65 is provided in conduit 63 for control purposes. Due to the fact that conduits 63 and 64 are made of insulating material and the air passing through them is dry,

the varied requirements of practical use.

electrode means 25 is efficiently insulated from separator 62. This makes it possible to maintain a high voltage potential upon electrode means 25 and, at the same time, maintain separator 62 at ground potential.

The length or lengths of insulating conduit employed is such that appropriate insulation, with a suitable safety factor, is achieved between the high voltage electrode structure and the other parts, such as the compressor 60 and air conditioner 62. At the same time the flexibility of conduit 64 gives adequate range of change of ver'- tical position of the electrode means 25 to meet Thus the electrode elements 26' are effectively maintained at the high potential, are caused to move at a suitable linear rate of movement above the conveyor i5, and as they move or rotate dried air is discharged in a general downward direction through the nozzles on the electrode elements.

Juxtaposed to the electrode means 25, and spaced downwardly therefrom, is a condenser plate 10 made of any suitable sheet metal. Plate 10 preferably extends horizontally and is adjustably mounted in any suitable manner relative to the base frame ID, as by the manually operable screws H and 12, whereby the plate 10 may be raised or lowered as desired. Plate 10, being thus mounted on the base frame in, is at ground potential and coacts with the rotating high potential electrode 25.

With this relation ofparts, the air space or region between the plane of the lower ends of the electrode elements 26 and the plane of the product-carrying side of the belt i5 is electrically stressed and breaks down. With an appropriate spacing between the plane of the belt and the condenser plate 10, the above-mentioned region of breakdown becomes a region of corona-like discharge emanating from the discharge electrode elements 26. Because of the large number of electrode elements 26 and particularly because of the relatively high speed of movement thereof, in conjunction with the relatively high frequency of the potential applied by the transformer 28--29, this corona-like discharge is made up of such a multitude of discharge or corona-like streamers, as to give the appearance, to the naked eye, of a highly dense or solid annular-like mass of corona discharge. The products l6 are moved through this discharge by the conveyor I5 so as to be subjected to the discharge which seeks out the various possible forms of insect life in the product. Such forms of insect life have a substantially infinite permittivity and being in effect electrically conducting are thus destroyed.

Preferably complete rupture does not take place due to the fact that I maintain the air space between the products in the treatment zone and the condenser plate 10 (the two forming in effect a capacity) large enough safely to withstand the maximum voltage applied by the transformer. In a similar manner andby appropriate relative adjustment of the parts, I am enabled also to preclude puncturing of pasteboard or other wrappings or enclosures where the products undergoing treatment are packaged.

Preferably, I provide means for coacting with the moving electrode elements 26 for preventing straying of the dielectric flux and hence the discharge emanating from the electrode elements and thus make the above-mentioned region of discharge stillmore concentrated or more dense. Accordingly, underneath the product-carrying side of the belt I5, I provide a support 13, pref- 'erably in the form of a metallic plate or casting spaced downwardly from the product-carrying side of the belt and supported from the side beams 23-24 in any suitable manner, as by brackets 14-14 made preferably of insulating material. Plate-like member 13 may thus be made to extend substantially parallel to the condenser plate 10, and the return side of the belt I 5 may pass between these two parts.

In the member 13 I provide a series of pockets or sockets l3 preferably arranged in a circle of a diameter substantially the same as the diameter of the circle of the rotating electrode elements 26 and, for reasons about to be noted, I lessen the numberof such sockets and hence of the parts which they are to receive.

Seated in each of these sockets is an electronic conduction device 15. These devices 15 are preferably made in the form of T-shapedglass or quartz tubes, the lower end of the vertical portion '15 of which is an'electrode 15 suitably grounded or connected to the plate member 13. The cross-bar or upper horizontal portion 15 of each tube 15 may be of any suitable length, and may even be arcuate (see Figure 2) and if so the. radius of curvature is substantially that of the circle of the sockets I3 in which the tubes I5 are mounted. When arranged as shown in Figures 1 and 2, therefore, the cross-bar portions 15 of these tubes 15 virtually abut end to end and do so in a circle commensurate in diameter with that of the rotating electrode elements 26. The interior of the tubes 15 is filled with a suitable gas at appropriate pressure suchas, for example, neon at a pressure of five or six millimeters and, being positioned in the highly stressed dielectric field between the metallic electrode structure 25 and the condenser plate 10, the tubes 15 become conductive, their gaseous contents becoming ionized and breaking down under this stress. The conductive gaseous content, due to the configuration of the tubes 15, and particularly immediately underneath that portion of the belt l5 that is in the treatment zone, is given the effective shape of a substantially continuous or uninterrupted circle (see Figure 2) coaxial with and directly juxtaposed to the circle of rotating electrode 25*.

Accordingly, the above described annulus of discharge of corona streamers, otherwise tending to stray or spread out as it impinges upon the belt I5, is concentrated by this circular shape of the efiective portions of the conduction tubes 15 and is caused to be directed toward and confined within the efiective circle of the tubes 15. This counteracts the tendency to stray or spread out and thus insures highly concentrated and uniform action throughout the mass or thickness of the products to be sterilized. With the tubes 15 thus in action, complete rupture or breakdown of the capacity circuit of the transformer 28-49 may be prevented by the effect of the parts 10 and I3 which, by appropriate adjustment of the part 10, form an air condenser whose proportions are such that breakdown therebetween at the maximum voltage of the transformer does not take place.

A circular aperture 22 is provided in plate 22 directly below and the same size as electrode 25 Fitted in this aperture, and having its upper face flush with the upper face of plate 22, is a quartz disc 16. Quartz disc 16 acts as a support means for the portion of belt l5 which is under electrode 25*. The use of quartz disc I6 reduces the stress upon tubes I5 and they may, therefore, be made of glass.

During operation, electrode elements 26 are continually cooled by the dried air passing from the driving motor. This cooling prevents deterioration of electrode elements 26, and specifically prevents particles of metal from flying from the tips thereof. At the same time, the treatment zone below the ends of the electrode elements 26 is kept free from small particles of material, such as metal, by the passage of the air. This avoids any possibility of an are which might be caused by a particle of metal remaining withinthe treatment zone.

Should any adjustments be necessary for any reasons, such adjustments may readily be made. For example, if it is desired to raise or lower the electrode means 25, the adjustable connection of the supporting beam structure 35 to the frame extensions I l and I2 isappropriately manipulated orset. This will raise or lower the fluid motor with its electrode elements 26, the flexible conduit section 64 permitting freedom of such change in position of the structure 2526, while maintaining dependable electrical isolation of the fluid motor and electrode elements from the other parts of the apparatus. Also, the raising or lowering of the condenser plate 10 may be readily achieved. Either of these adjustments or both in conjunction with each other may be utilized to accommodate the apparatus to various electrical and mechanical requirements or conditions as well as to the particular characteristics of the material or product undergoing sterilization.

Furthermore, the apparatus will be seen to be mechanically and electrically simple, compact and reliable in action. The fluid motor, for example, is of simple and dependable construction, is of a character such that it does not easily get out of running order, and is in these and other ,respects well adapted for coaction with the other parts of the apparatus. Moreover, 'it will be seen that insulation difliculties are dependably and inexpensively overcome, without sacrifice of dependability and efficiency of sterilizing action. And it will thus be seen that there has been provided in this invention an apparatus in which the objects hereinbefore noted together with many thoroughly practical advantages are successfully achieved.

As many possible embodiments may be made of the mechanical features of the above invention, and as the art herein described might be varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In electrical treating apparatus, in combination, an electric discharge circuit comprising a source of suitable potential, spaced means between which electric discharge takes place, one of said means comprising electrode means connected to the high potential side of said source, and condenser means incapable of breakdown at the voltage of said source, said high potential means being mounted to move along a certain path, fluid-driven motive means operable by a non-conductive fluid for moving said movable electrode means, means for supplying non-conductive operating fluid to said motive means, and means including solid dielectric conduit means connecting said fluid-supplying means to sai fluid-driven motive means.

2. An apparatus like that of claim 1 in which the means for supplying operating fluid is a means providing air under pressure, there being moisture-removing means interposed between the fluid supplying means and the fluid-driven motive means.

3. An apparatus like that .of claim 1 in which the means for supplying operating fluid is a pump for maintaining the fluid under pressure.

4. An apparatus like that of claim 1 in which the meansfor supplying operating fluid is. a

pump, there being an electric motor driving said,

, means between which electric discharge takes place, one of said spaced electrode means comprising a rotatable support having a vented electrode element directed toward the other spaced electrode means, and an air motor related to said rotatable support for rotating the latter, said air motor exhausting through said vented electrode element.

'7. In an electrical treating apparatus, in combination, an electrical discharge circuit compris ing a source of potential and spaced electrode means between which discharge takes place, and means for carrying material to be treated between the electrodes in the path of the discharge, in which one of said electrode means comprises an insulating support member, a movable electrode, fluid pressure motor means supported from the insulating support and connected to the movable electrode to drive the same, and conduit means for supplying non-conductive fluid under pressure to said motor means and comprising a substantial length of solid dielectric conduit whereby said motor means may be kept at the potential of the electrode.

8. In an electrical treating apparatus, in com bination, an electrical discharge circuit comprising a source of potential and spaced electrode means between which discharge takes place, and means for carrying material to be treated between the electrodes in the path of the discharge, in which one of said electrode means comprises a movable carrier having electrode elements projecting therefrom for concentrating the discharge, fluid-pressure motor means comprising a stationary elementand a driven element to which the carrier is connected, and exhaust connections from said fluid-pressure motor means to exhaust a ble t of fluid into the discharge space.

9. In an electrical treating apparatus, in combination, an rlectrical discharge circuit comprising a source of potential and spaced electrode means between which discharge takes place, and means ior carrying material to be treated between the electrodesin the path of the discharge, in which one of said electrode means comprises a movable carrier having electrode elements projecting therefrom, each of said electrode elements having a tubular passage extending longitudinally therethrough from the interior of the carrier to the tip thereof, fluid pressure motor means within and adapted to drive said carrier and exhausting into said passages whereby the exhaust fluid discharges from the tips of the electrode elements into the discharge space.

10. In an electricaltreating apparatus, in combination, an electrical discharge circuit comprising a source of-potential and spaced electrode means between which discharge takes place, and means for carrying material to be treated between the electrodes in the path of the discharge, in which one of said electrode means comprises a rotatable carrier having electrode elements projecting therefrom for concentrating the discharge, said elements having longitudinal passages therethrough, fluid jet means on which the carrier is rotatably mounted and a turbinelike rotor integrally connected to the carrier and having spaced vanes adapted to cooperate with the jets to utilize the fluid pressure for rotation of the carrier, and said vanes forming channels which at their ends communicate with said passages in the electrode elements, whereby fluid from between the vanes is exhausted through said electrode elements into the discharge space.

11. An apparatus like that of claim 6 in which there is a source of air under pressure connected to said air motor through non-conductive conduit means.

12. In electrical treating apparatus, in combination, an electric discharge circuit comprising a source of suitable potential, spaced means between which electric discharge takes place and between which a product to be treated is subjected to said discharge, merns for holding a product in the space'between said spaced means thereby to be subjected to said discharge, one of said spaced means comprising discharge electrode means, and means directing a blast of air into the discharge region to deionize the air therein or to displace ionized air.

13.. An apparatus like that of claim 12 in which the air blast means includes a source of air under pressure, and orifice means associated with the discharge electrode means for discharging air from said air source.

14. An apparatus like that of claim 12 in which the air blast means includes an air turbinefor effecting movement of the discharge electrode means, the air expended in said turbine being directed through said air blast means.

15. In electrical treating apparatus, in combination, a source of high potential, capacity-forming means connected thereto and including a movable electrode structure and means juxtaposed thereto for coaction therewith for producing an electric discharge, means for subjecting a product to be treated to said discharge, said electrode structure having a tube-like discharge electrode, and means for causing an air current to flow therethrough.

16. In electrical treating apparatus, in combination, a source of high potential, capacity-forming means connected thereto and including a movable electrode structure and means juxta- Posed thereto for coaction therewith for producing an electric discharge, means for subjecting a product to be treated to said discharge, said electrode structure, having a discharge electrode with an aperture therein, and means causing the flow of air current out of said aperture.

17. An electrical treating apparatus comprising an electrical circuit including a source of potential and spaced electrode means between which discharge takes place and means for carrying material to be treated between the electrodes in the path of the discharge, which is characterized by one of said electrode means comprising projecting electrode elements having longitudinal passages therethrough for passage of fluid and means for passing a stream of fluid through said electrodes whereby to carry ionized air from the discharge space. 18. In an electrical treating apparatus, in combination, an electrical discharge circuit comprising a source of potential and spaced elec-' trode means between which discharge takes place, and means for carrying material to be treated between the electrodes in the path of the discharge, in which one of said electrode means comprises electrode elements movable in a predetermined path, and another of said electrode means comprises electronic conduction tubes serving as electrode elements, said tubes extending in a direction substantially at right angles to the path of movement of said movable electrode elements, but there beingportions upon the ends of said tubes which extend in a direction substantially parallel to said path.

19. In electrical treating apparatus, in combination, means for holding a product-to be treated,

electrode means spaced to one side of said firstmentioned means, T-shaped electronic conduction means on the other side of said first-mentioned means, a source of relatively high potensaid T-shaped electronic conduction means having their horizontal portions alined in juxtapm sition to and substantially parallel to the path of movement of said electrode means.

22. An apparatus like that of claim 19 in which the electrode means is rotatable, means is provided for rotating said electrode means, and said T-shaped conduction means are in sumcient number and with their top portions alined to form substantially a circle commensurate with the circle defined by the rotating electrode means.

23. The method of treating materials by electrical discharges which comprises producing an electric discharge by a pulsating potential, sub- Jecting a product to be treated to said electric discharge, and deionizing air in the discharge space by an air blast directed into the latter.

thereby displacing ionized air to eilect discharge at a higher point in the instantaneous 'voltage characteristic upon the succeeding pulsation.

24. In electrical treating apparatus, in combination, asource of high potential, capacityforming means connected thereto and including a movable electrode structure and means juxtaposed thereto for coaction therewith for producing an electric discharge within a treatment zone, means for moving a product through said treatment zone, said electrode structure having a' tube-like discharge electrode, and means for causing an air current to flow therethrough.

25. In electrical treating apparatus, in combination, a. source of high potential, capacityforming means connected thereto and including a movable electrode structure and means juxtaposed thereto ior coaction therewith for producing an electric discharge within a treatment zone, means for moving a product through said treatment zone, said electrode structure having a discharge electrode with an aperture therein, and means causing the flow of air current out of said aperture.

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