US1230708A - Vapor electric apparatus. - Google Patents

Description

R. C. HEWT.

VAPOR ELECTRIC APPARATUS.

APPLICATION FILED oc. I, 1912.

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UNITED STATES PATENT OFFICE.

PETER COOPER HEWITT, OF RINGWOOI) MANOR, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, T I COOPER' HEWITT ELECTRIC COMPANY, OF HOBOKEN. NEW JERSEY, A CORPORATION OF NEW JERSEY.

VAPOR ELECTRIC APPARATUS.

Specification of Letters Patent.

Patented Julie 19, 1917.

Application led October 1, 1912. Serial No. 723,303.

To all whom t may concern.'

Be it known that I, Parnu COOPER Hnwrr'r, a'citizen of the United States, and resident or Rinvwood Manor, county of Passaic,

State or New Jersey, have invented certain new and useful Improvements in Vapor Electric Apparatus, of which the following is a specification. U

This invention relates to vapor electric apparatus of the vkind comprising an exhausted container or envelop provided with positive and negative electrodes insulated from each other with reference to the walls of the container, the negative electrode being composed of material of such a nature that the'particles thereof will reunite physically and electrically on contact with one another after separation under the conditions obtaining within the container.

The invention more particularly relates to rectitying apparatus of the above general character which is adapted to operate with large currents of the character utilized in commercial service.

The general nature and operation of apparatns of this character is now well known and more particularly the fact that a characteristic dropof electric potential in mercury vapor apparatus occurs between the positive and negative terminals of the apparatus which may be equal in amount to about fourteen volts when the resistance of the vapor column is but small.

I have found that the drop of potential above referred to may be divided into three main component parts located respectively at the surface of the positive electrode, within the luminous vapor column and in the region adjacent to the surface of the negative electrode.

I have further discovered that the last of these three components can be further subdivided into three portions, namely, a drop of potential at the actual surface of the negative electrode, a drop of potential somewhat uncertain in nature and amount within a region of which the negative ame or are is y umn is eliminated.

The present invention contemplates a new disposition of the positive electrode with reference to the negative electrode and to the various regions in which falls of potential occur, as has been above described, and my invention consists essentially in placing the positive electrode in such proximity to the negative electrode that the positive electrode is within the region in which, what I have termed above the negative electrode component or' the fall of potential, occurs, so that the luminous portion of the vapor col- As the result of this arrangement a relatively great reduction in the tota-l fall of potential between thel terminals of the apparatus is eii'ected which can be accounted for by certain of the reactions above referred to being eliminated or annulling one another.

The invention is illustrated in the acconr panying drawings, of which Figure l is a sectional view in side elevation showing one form of vapor electric apparatus embodying the invention.

Fig. 2 is a plan view partly sectional on the line II-II of Fig. l., viewed from above; Fig. 3 being a similar view from below.

Fig. 4 is a pla-n view of the positive electrode of the apparatus shown in Fig. l, viewed from below.

Referring now to the drawings, the rectit'ying apparatus comprises a cylindrical metal container l, of steel, Norwegian iron or other suitable material, the base portion 2 of which serves as the receptacle for the mercury or other vaporizable liquid conducting material indicated at 3, which constitutes the negative electrode of the apparatus. The top of the container 1 is closed by a composite cover comprising a flanged ring i of mild steel or other suitable material supported upon an annular rib 5 secured to the upper portion of the container l. The ring 4c supports an annular disk 6 having a lower projecting portion 7 the outer edge of which is beveled to correspond with the inner edge of the ring e. The disk 6 is also provided with an upwardly extending cylindrical portion 8 the outer surface o-f' which is screw-threaded. Upon the disk 6 an insulating bushing 9 oi porcelain or other suitable nonconducting material is' supported, a beveled shoulder upon which is arranged to be clamped firmly in engagement with the disk 6 by means of a the insulating ring 9. The positive electrode 12 is arranged to be water-cooled, being provided withan internal su )ply pipe 16 the lower portion of which is oli cup-shaped form located within the corresponding portion 13 of the positive electrode 12. The lower edge of the cup-shaped ortion of the supply pipe 16 is provided wit two or more nozzles as shown clearly at 17in Fig. 4, these nozzles being so arranged that the cooling liquid passing through the supply pipe 16, as 1ndicated by the arrows in Fig. 1, has a tangential motion imparted thereto when issuing from the nozzles 17y into the interior of the positive electrode 12. The cylindrical portion 14 of the latter is provided with an outlet pipe 18 for the cooling water, which may be caused to circulate through the hollow electrode 12 by any suitable means, such as a pump. The lower portion 2 of the metal container 1 containing the negative electrode is also surrounded by a cooling jacket 19 provided with inlet and outlet pipes 20, 21 respectively. l

Located within the space between the positive electrode 12 and the negative electrode 3 is a cooling device 22 comprising a hollow circular casing of convex form, to one edge of which cooling liquid is supplied through a pipe 23, an outlet pipe 24 at the opposite edge of the cooling device 22 being arranged to project within the hollow casing to a point near the upper inner surface of the latter, as

'clearly shown in Figs. 1 and 3. The pipes 23 and 24 are passed through thel container 1, a tight joint being insured by any suitable packing. An insulating shield 25 is provided, the lower edge of which is below the surface of the negative electrode 3, this shield being held in position by suitable clips 26 and serving to limit the active area of the negative electrode in a manner now well known in the art. An auxiliary or starting positive'electrode 27 is also provided, comprising a horizontal tubular portion 28 projecting through a suitable gastight bushing 29 in the wall of the cooling jacket 19 and a tubular arm 30 extendingat right-angles from the portion 28 and terminating in a solid contact member 31. The portions 28 and 30 of the starting electrode are surrounded by a tubular cooling jacket 32 preferably of quartz or other refractory material, the cooling liquid for this electrode passing through the tubular member 28,0011- stituting the conducting portion of the electrode and from thence through a hole in the tubular arm 30 into the interior of the quartz jacket 32, the outer end of which is in open communication with the cooling jacket 19 for the negative electrode.

r1`he operation of the starting electrode will be readily understood without further description, as by rotatin the horizontal portion 28 of the electrode rom the exterior of the apparatus the solid contact member' 31 can be brought into engagement with the surface of the negative electrode within the insulating shield 25, the rotation in the opposite direction serving to withdraw the contact member 31 from the negative electrode and initiate a discharge within the container of the apparatus.

As will be seen from Fig. 1 of the drawings, the positive electrode 12 is located much nearer to the negative electrode 3 than has `hitherto been customary, so that as explained above the positive electrode will lie within a certain critical distance of the negative electrode, resulting in a considerably greater rcduction in the total .fall of potential between the terminals of the apparatus.

1t is unnecessary to determine or describe i'ully the exact theory upon which this reduction in the total potential depends, but it is found in practice undoubtedly to occur' when the positive electrode is placed much nearer to the negative electrode than is usual in apparatus of this description using small currents, the exact distance separating the two electrodes being dependent upon the amount of current traversing the apparatus and the degree of rarefaction of the vapor. The .intermediate cooling device 22 also serves to modify the distance necessary between the positive and negative electrodes, the general tendency of the cooling effected in this manner being to increase this distance.

It should be noted that the reduction in the fall of potential above described is not due to a reduction in the length of the vapor column, since, if the electrodes be gradually moved toward one another the fall of potential between the terminals of the apparatus remain substantially constant until the positive electrode is within a certain critical distance of the negative electrode which distance varies as above stated. When this critical distance is reached a sudden marked decrease in the fall of potential across the terminals of the device occurs and the luminous effect of the vapor column disappears.

As an example of the actual reduction in the fall of potential obtained according to this invention I may mention that in a particular apparatus the normal drop of potential across the terminals was fourteen volts, and by reducing the distance between the positive and negative electrodes to the critical distance above referred to the drop of potential suddenly decreased to somewhat less than eight volts.

- By utilizing this reduced fall of potential a corresponding decrease inthe total energy lost in the apparatus is obtained.

It will be understood that the inventionV is not limited to any particular type of electrede nor to any specific proportions or location of the electrodes relatively to one another and that all arrangements in which the electrodes are so disposed as to utilize the decreased fall of potential above indicated fall within the scope of the invention.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, l. declare that what l claim is- 1. A vapor electric apparatus comprising an exhausted container, positive and negative electrodes therein, the extremity of the positive electrode being located at a critical distance from the negative electrode, the said critical distance bein the distance between the negative electro e and a point in the vapor column at which a sudden marked decrease in the fall of potential across the terminals of the device occurs, as compared with the drop when the electrodes are more remote from each other.

2. A vapor electric apparatus comprising an exhausted container, positive and negative electrodes therein, the extremity of the positive electrode being located at a critical distance from the negative electrode, the said critical distance being the distance loetween the negative electrode and a point in the vapor column at which a sudden marked decrease in the fall of potential across the terminals of the device occurs, and a cooling device located intermediate the two electrodes and serving to modify the said critical distance.

3. A vapor electric apparatus comprising an exhausted container, positive and negative electrodes therein, the positive electrode being located in proximity to the negative electrode and having a suitable stem for connection with the external circuit, a tubular device inside the positive electrode, separated therefrom by an intervenin space, and conforming generally to the s ape of the positive electrode and its stem for permitting the circulation of a cooling fluid, and a tube carrying a cooling iluid outside the positive electrode and .passing in front thereof.

4. A vapor electric apparatus comprising an exhausted container, positive and negative electrodes therein, the positive electrode being cup-shaped and located in proximity to the negative electrode and having a suitable stem for connection with the external circuit, a tubular device inside the positive electrode, separated therefrom by an intervening space, and conforming generally to the shape of the ositive electrode and its stem for permitting the circulation of a cooling fluid, and a tube carrying a cooling fluid in front of the positive electrode and in proximity thereto along the entire face of the said electrode.

5. ln a vapor electric apparatus comprising an exhausted container, positive and negative electrodes therein, an insulating shield within the negative electrode for limiting the active area thereof, in combination with starting devices for the said apparatus, comprising a conductor sealed through the Wall of the apparatus and bent into contact with the negative electrode.

6. in a vapor electric apparatus comprising an exhausted container, positive and negative electrodes therein, an insulating shield within the negative electrode for limiting the active area thereof, in combination with the starting devices for the said apparatus, comprising a conductor sealed through the wall of the apparatus and bent into con'- tact with the negative electrode, and a cooling jacket surrounding the starting conductor.

Signed at New York in the county of New York and State of New York this 27th day of September A. D. 1912.

PETER COOPER HEWITT.

Witnesses:

JOHN W. CRANDALL, Trios. H. BROWN.

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