US 940430 A
Description (OCR text may contain errors)
r Y W. H. CHAPMAN. PROCESS AND APPARATUS FOR NEUTRALIZING STATIC ELEGTRIGITY.
' APPLICATION FILED APR. 2 1906.
940,430. 1 Patented Nov. 16, 1909.
UNITED STATES PATENT orrion.
WILLIAM H. CHAPMAN, F PORTLAND, MAINE, ASSIGNOR TO CHAPMAN ELECTRIC NEUTRALIZEB COMPANY, OF PORTLAND, MAINE, A CORPORATION OE MAINE.
PROCESS AND APPARATUS FOR NEUTRALIZING STATIC ELECTRICITY.
, Specification of Letters Patent.
Application filed April 2, 1906. Serial No. 309,352.
To all whom it may concern:
Be it known that I, WILLIAM H. CHAP- MAN, a citizen of the United States of America, and a resident of Portland,'Maine,i have invented certain new and useful Improvements in Processes and Apparatus for Neutralizing Static Electricity, of which the following is a specification.
My invention relates to a process and apparatus for neutralizing static electricity in moving material and it is particularly di-' rected to certain improvements in the process shown in my Patent No. 777 ,598 dated Dec. 13, 1904C and the'apparatus used for carrying out that process.
In this process I have made use of an alternating electric charge of high voltage applied to a wire or other conductor containing small points and supported in close proximity to the moving paper or other like material. p n
The process herein set forth is a modification of the process set forth in my application No. 292,388 filed Dec. 18, 1905. y
In using my process for the treatment of textile yarns and other forms of textile materi I have found that in many cases it was not practicable to locate the wire or other cond tor near enough to the work so that the i the condu'c. or would reach the material to be treated;
Thefnbject of my present invention is to so that the ions discharged from the conductor the process and the apparatus will travelv a considerable distance, taking effect as far away as 18 inches in some cases and enabling me to locate my conductor at a convenient point abouttextile machinery of various kinds which is as a rule so crowded with parts that there is little room for such devices as this. I accomplish this object by using a direct charge of high voltage on the conductor, modifying the effect to prevent overcharging of'the material by partially surrounding the conductor with a conducting envelop or slotted tube con-' nected to earth. A free or open space is left in the envelop of varying width according to the distance the ions have to travel and I have found from'experience that with a conductor in a slotted tube and charged with a high tension direct charge, there is a certain fixed width of slot which may be used for different distances through which sufficient ent ed by the discharge from electricity will pass to neutralize the electricity of the goods without overcharging them as would be the case if the conductor wasopen or unclosed.
Another object of my invention is to find a conductor with sufliciently fine points or surfaces which can be cheaply made and strong and substantial for practical use in mills &c. as I have found that a single wire when the radiation took place from 1ts sidesoxidized rapidly under the'action' of the ozone produced. This object of my invention I carry out by the use of a substantial metal rod preferably steel or iron having a tubular covering with fine points or projections formed preferably of a thin strip of copper with angular cuts inits edge and wound spirally into the form of a tube with angular and poipted projections.
I illustrate the several features of my invention by means of the accompanying draw mg in which:
Figure 1 1s a central longitudinal section showing my conductor as I prefer to make.
it, Fig. 2 is an enlarged cross section through the same, taken on the line a: w of Fig. 1.
Fig. 3 is a detail of the copper strip before winding and Fig. 4 is a diagram illustrating the application of my process to moving yarn.
Considering Fig. 4-, J represents a -Wimshurst machine or other source of high tension direct current electricity connected by a wire lc'to an insulated conductor 11. passing through a tube m of brass or other conduct- Patented. Nov.16,1909L ing material connected to earth with a lon itudinal slot 0 int-he under side of the tu e. Strands of yarn p are represented as passing along under the tube mand the ions discharged from the conductor by the high ten: sion charge are represented as passing from the conductor through the slot 0 onto the yarn as it passes by. It isunderstood that the electricity supplied to the wire a is of opposite polarity to that generated in the yarn in its process of manufacture, the electricity being generally generated in the yarn and other textile material 7 by P3881110 through rolls where it becomes compressed? The ions discharged by the conductor neutralize the electricity of the yarn and the yarn is prevented from getting an overcharge by the presence of the metal partially surrounding the conductor. The slot 0 is of a certain wldth according to the distance of slot will have to be and the more ions it will be necessary to release to dtuthe same work.
the yarn from the conductor, so that it allows just the right uantity to pass to neutra'lize' the yarn wit iout giving it an overcharge. The reason the width of the slot limits the charge which goes to the material is as follows: The ions are given off in all directions from the conductor and striking directly on the inner surface of the conductor the charge which they contain is conducted to earth. Those which are given 01f in the direction of the slot will be diverted and conducted away by the tube when there is no charge of opposite electricity in the ma terial to attract them. l/Vhen however there is a charge in the material of opposite polarity to the ions given olt' by the conductor, the latter are drawn or attracted through the slot by a force stronger than that by which they are attracted to the tube. Thus while 7 the charge is in the material the ions will be latter becomes neutral the attraction of the tube takes effect and diverts the ions to the tube and the charge is delivered on to earth. It is evident that thefarther away the material is from the conductor the larger the If the slot is too wide there will be an escape of ions through the slot when the material is in a neutral condition and consequently it will receive an overcharge of the same kind of electricity as that given oil by the conductor. For this reason as already stated, there is generally a certain standard Width of slot which is efiective at a given distance. I
find from experience that the width of the slot does not have to be regulated with absolute accuracy as a slight over or under charge is not injurious tothe yarn or other textile material. The practical form of conductor which I use for this class of work is shown in Figs. 1, 2 and 3.
For supporting the insulated conductor I make use of a tube preferably, of brass, laterally perforated with holes or when the direct current and long distance process is used with a longitudinal slot regulated in width according to the distance the ions have to travel. As here shown, 1 use a brass tube having a slot .9 in its underside and having it for the purpose of protecting the operatorfrom getting a shock or spark and a check nut 0 is located on the rod just insideof the bushing. At the opposite end of the tube the rod projects through the bushing t) in like manner, with a check nut c on the inside conductor. The discharging or radiating points are provided by means of a tubular coveringor envelop which is slipped over the rod 18 and which is provided withnumerous projecting points or fine surfaces. As here shown, I form this tubular covering by means of a strip of thin copper l) in the edge of which is cut a series of angular cuts. The stripis wound spirally about a form to form a tube and is slipped on in sections over the rod B, the pointed portions 6 projecting outward from the body of the strip to form radiating points which will be unatiected bythe action of the ozone. in the centerof the tube is shown an insulatin guide 2' for supporting the rod. This form of conductor can be made up in lengths to suit the job, the tube D can be put on in short sections if desired and the slot cut according to the distance of the work from the conductor. When the alternating charge is to be used as in the treatment of paper when the conductor can be placed near the work, the tube will be perforated instead of slotted.
l: claim 1. The herein described apparatus for rcmoving static electricity whichconsists of a tube of conducting material connected to earth and having a longitudinal slot therein, a longitudinally disposed insulated conductor within said tube and means for supplying a high voltage charge to said conductor.
2. The herein described conductor for neutralizing static electricity which consists of a tube having one or more openings through the sides thereof, an insulating bushing at each end, a metal rod extending through said tube and said bushings and a tubular covering for -said rod having projecting points for discharging high voltage electricity.
3. The herein described conductor for use in neutralizing static electricity which con sists of a laterally perforated tube having lot) extending longitudinally through it an insulated conductor composed of a metal rod 5. The herein described conductor for use in neutralizing static electricity which consists of a laterally perforated tube having av longitudinally disposed insulated metal rod therein, said rod having a tubular covering composed of a spirally wound strip of thin metal having angular slits in its edge forming pointed sections which are bent outward to form discharging points and edges.
6. The herein described conductor to be used for removin static electricity which consists of a per orated tube connected to earth, an insulated bushing in each end, a screw threaded metal rod extending centrally through said tubeand said bushings,
a nut on said rod on the inside and the outside of each bushing, one of said external threaded stud screwed into the other external nut and abutting against the end of said rod, and a tubular covering for said rod havin fine projecting points or surfacesf 7. The herein described conductor for disity consisting of a metal rod having a tubular covering composed of a spirally wound strip of thln metal having angular slits in its edge forming pointed sections which are bgnt outward to form discharging points or e es. f gigned at Portland, Maine this 24th day of March 1906. 4
WILLIAM H. CHAPMAN.
nuts being of insulating material, a screw S. W. BATES, MARY A. DoNALnsoN.
charging or radiating high voltage electric-