Description

Patented December 6 |898.
T B KINRAIDE
HIGH FREQUENCY INDUCTION APPARATUS.
(Request med mr. 4, 189s.)
(No Model.)
Kinraide Patent Drawing

UNITED STATES PATENTS.
THOMAS B. KINRAIDE, OF BOSTON, MASSACHUSETTS.
HIGH FREQUENCY INDUCTION APPARATUS.
SPECIFICATION that is part of Letters Patent No. 615,653, dated December 6, 1898.
Application filed on March 4, 1898. Series No. 672.531. (No model.)
To all who may be interested.
Let it be known that I, THOMAS B. KINRAIDE, of Boston, Suffolk County, Commonwealth of Massachusetts, have invented an improvement in high-frequency induction apparatus, of which the following description, in connection with the accompanying drawings, is a specification, such as letters on drawings that represent similar parts.
My invention is an improvement on induction coils and has for its principal object the provision of an apparatus capable of unlimited high frequency without danger of self-destruction or breakdown.
Induction coils, as ordinarily constructed, are wound in the form of a disc, the discs being placed side by side, usually in the form of a column or tubular on a central core, so that of course the coils are shorter and therefore offer less resistance on centers. of the disks or next to the core, and the greatest potential is on the outside-ft'. that is, on the circumference of the disk, where the coils are longest. I have completely departed from this principle and have produced a flat coil in which the highest voltage is on the shortest turns and the lowest voltage is on the longest turns, or, in other words, the voltage increases inversely as the resistance.
In its simplest form and preferred embodiment, my invention comprises a coarse few-turn primary and a thin many-turn secondary, preferably arranged coaxially, the primary being confined to the low-voltage or circumferential portion of the secondary.
Details of construction and the most complete embodiment of my invention and the most surprising phenomena thereof will be set forth in the course of the following description, with reference to the accompanying drawings, and the invention will be more particularly defined in the appended claims. .
In the drawings, in which I have shown preferred embodiments of my invention, the figure is a central vertical section of a coil or simple apparatus, illustrating one form of my invention. Figure 2 is a top plan view of the same, on a reduced scale and partially schematic, to facilitate its understanding. figs. 3 and 4- are details in perspective of the insulators or separators used. Figure 5 is a view similar to Figure 1, showing a complete embodiment of my invention. Figure 6 is a top plan view thereof, partially schematic. Figure 7 is a fragmentary view showing a way of making the primary thick.
In a box A of any desired suitable shape and size, shown in Figs. 1 and 2 as circular and in Figs. 5 and G as oblongs with rounded ends, assemble a B primary and a C secondary, interposing a partition D, preferably glass, between the primary and the secondary, if desired, but may be omitted. The box A preferably has a removable bottom a and a top part a', Fig. 5, these parts being preferably made of vulcanite or other insulating material.
When a partition D is used, a projection d3 may be moulded, stamped or turned, if desired, on the inside wall of the box, on which the partition can sit, and for cleaning of the construction, the top it will also preferably rest on a similar ledge. The top and bottom may be screwed or otherwise attached to the edges of the walls or the edge of the box, although I want it to be understood that the details of the closing box can vary infinitely within my invention.
I wind the secondary C, of ??fine wire and any area desired, into a thin, flat disc and secure it by suitable means to one of the sides of the box, here shown as the upper side, the means being Here shown as comprising a plurality of glass rods c, arranged in pairs oppositely placed above and below the secondary and together constituting a holding grid. It is obvious that this grid can be made in any way, with parallel bars being preferred simply for convenience. Having correctly positioned the secondary between its holding rods or other holding devices that may be used, I preferably connect the secondary terminals with a current sufficient to raise the secondary to considerable heat and then pour a molten insulator into the box. compound E, preferably of rosin and beeswax, sufficient to fill the box and completely cover the secondary, preferably also covering the holding rods c, as indicated in the figures, holding the heat long enough to ensure that the rosin and the melted wax will have penetrated into each opening of the secondary and its neighboring parts. The primary is placed in position in the same way, except that a holding grid is not necessary for this, since the inherent rigidity of the thick wires prevents any buckling or warping of the same under the action of the heated insulating compound. The result is that when the insulating compound has hardened, the primary and the thin, flat disc of the secondary are completely isolated. holding the heat long enough to ensure that the melted rosin and wax have penetrated each inerstice of the secondary and its neighboring parts. The primary is placed in position in the same way, except that a holding grid is not necessary for this, since the inherent rigidity of the thick wires prevents any buckling or warping of the same under the action of the heated insulating compound. The result is that when the insulating compound has hardened, the primary and the thin, flat disc of the secondary are completely isolated. holding the heat long enough to ensure that the melted rosin and wax have penetrated each inerstice of the secondary and its neighboring parts. The primary is placed in position in the same way, except that a holding grid is not necessary for this, since the inherent rigidity of the thick wires prevents any buckling or warping of the same under the action of the heated insulating compound. The result is that when the insulating compound has hardened, the primary and the thin, flat disc of the secondary are completely isolated. insofar as the inherent rigidity of the thick wires prevents any buckling or deformation of the same under the action of the heated insulating compound. The result is that when the insulating compound has hardened, the primary and the thin, flat disc of the secondary are completely isolated. insofar as the inherent rigidity of the thick wires prevents any buckling or deformation of the same under the action of the heated insulating compound. The result is that when the insulating compound has hardened, the primary and the thin, flat disc of the secondary are completely isolated.
In view of the fact that my secondary is made of such fine wire and is in the shape of a thin disc, it needs to be held firmly with a grid-shaped support while pouring the wax, otherwise it will work. so
The rods c may be supported at their ends by glass blocks c', as shown in Fig. 4, or a more convenient construction is that shown in Fig. 8, where it will be seen that the rods are individually provided. of c2 heads and are attached simply by winding a piece of c3 silk thread around the ends of the heads. This last construction is extremely convenient. These glass rods, it can be seen, are also advantageous in holding thin or brittle conductors in various other relationships than those shown here.
It will be noted that the partition D is cut in its middle part, so that it will be understood that both sides, or in other words, the entire apparatus, are poured at the same time with the insulating mass. The compound I have mentioned is normally solid and therefore there is no tendency for the appliance to leak; but, on the contrary, it is substantially in one piece or solid, with no danger of loosening or damage. Furthermore, if for any reason any heating effect has occurred at any point in the apparatus, it is evident that the fusible insulating compound will soften or melt enough to cause it to automatically flow around the heated parts and maintain perfect insulation.
I prefer to use a primary made as illustrated in full lines in the figures, where it will be seen to consist of a flat helix of thick wire or metal, though it may be in other forms, for example, as indicated by dashed lines at B in Fig. Fig. This B propeller is conveniently made by sawing a piece of sheet metal to produce the shape shown (see Fig. 7), the air gap formed by the saw cuts is suflieient in practice to insulate the primary, especially when embedded in the insulating compound, as explained.
I have shown both the primary and the secondary as circular, although it will be understood that they may be square, oval, or any other desired shape, oval being preferable, for example, where a long spark is desired in an instrument of the shape shown in Fig. l.
In the above description, I have deliberately omitted all technical details of construction in order to present my invention in its general features and simplicity, although it will be understood that proper binding posts and connections will be provided, as indicated in Zr b3, Fig. .l, and that the other usual regulating features will be used in connection therewith, including a break, capacitor, el. The inner terminal of the secondary is shown at c4 extending on a central post el to a usual adjustable electrode a5, and the opposite terminal of the secondary is shown in Fig. 1 terminating in a thimble or ferrule c5 on a socket a6, which may contain any suitable electrode, an a7 sparking ring shown in its place.
Referring to Figs. 5 and G, it will be seen that I have provided two primaries B2 B, connected together at b4, and two secondaries C2 C3, electrically connected by a contact ring or ferrule c5 similar to that already described. The two primaries and secondaries are separated by an insulating block A', which constitutes a part of the case, and are embedded in an insulating compound exactly the same as that described in the simplest form of the apparatus shown in Fig. 1, being understanding that the primary and secondary connection cables are conducted through insulating tubes, as indicated in d8, Fig. 5. The internal terminal of each of the secondaries C2 C3 is connected to a central post a4, which contains an a5 electrode, as already described, and the c5 thimble or splint (shown in Fig. 5 as stopped by a plug a9) is adapted to receive a discharge ring a7 or some other form of electrode, although it will normally be stopped by the plug, as shown. The primary is restricted to the circumferential portion of the secondary, that is, it is located in the vicinity of the outer or largest turns of the ring-shaped secondary that has a large central opening. In addition to this, I make the primary relatively short and of large cross-sectional area, the latter feature giving the primary a large static or capacitor capacity. There is also a complete absence of any cores or anything of that nature that produces slowness. The result is that I can get extremely high frequency without destructive heating. The primary is restricted to the circumferential portion of the secondary, that is, it is located in the vicinity of the outer or largest turns of the ring-shaped secondary that has a large central opening. In addition to this, I make the primary relatively short and of large cross-sectional area, the latter feature giving the primary a large static or capacitor capacity. There is also a complete absence of any cores or anything of that nature that produces slowness. The result is that I can get extremely high frequency without destructive heating. The primary is restricted to the circumferential portion of the secondary, that is, it is located in the vicinity of the outer or largest turns of the ring-shaped secondary that has a large central opening. In addition to this, I make the primary relatively short and of large cross-sectional area, the latter feature giving the primary a large static or capacitor capacity. There is also a complete absence of any cores or anything of that nature that produces slowness. The result is that I can get extremely high frequency without destructive heating. the latter feature gives the large main capacitor or static capacitance. There is also a complete absence of any cores or anything of that nature that produces slowness. The result is that I can get extremely high frequency without destructive heating. the latter feature gives the large main capacitor or static capacitance. There is also a complete absence of any cores or anything of that nature that produces slowness. The result is that I can get extremely high frequency without destructive heating.
The primary is located entirely or mainly on one side or next to the circumferential portion of the secondary and there is no core of magnetic material, but only electrical inductive action, a bunching or condensation of the lines of force results in the center of the secondary in the form obvious vertical, so that the potential or voltage on the inside of the coil is high and that on the outside is low. The intensity of the electric field increases enormously in the center of the coils and almost all the lines of force of the whole coil are concentrated in this central part of the coil, and the construction is such that this condition is maintained, i.e., there is a huge propelling discharge from the electrode in the center of the coil and there is IOO IIO
THAT
there is hardly any discharge from the outer electrode of the same in c5. This will be understood with reference to Fig. 1, where I have indicated the discharge effects with dotted lines. The discharge takes place or can take place as radiant flames caught by a ring, as shown in Fig. 1, or by removing the ring or turning the electrode a5 to some other angle, this radiant discharge simply shoots out into space.
A great advantage besides the already mentioned high frequency and huge discharge is that there is no fear of melting the coil. Hitherto, in induction coils it has been necessary to exercise extreme care in regulating the discharge terminals to avoid too great a resistance between them, otherwise the apparatus would quickly short-circuit and ruin itself, whereas in any present invention all this ends.
While I have herein described a preferred embodiment of my invention, I wish it to be understood that many changes and rearrangements can be resorted to without departing from the spirit and scope of the invention and that I am not otherwise limited to a relatively large central opening. said secondary coaxial, as and for the established purpose.
2. An induction apparatus comprising a winding producing an exciting field and an electrical conductor excited by it, said conductor having a plurality of turns of different lengths, said field winding being located adjacent to the longest of said turns and the shortest of said laps. turns having the highest voltage, substantially as described.
An induction apparatus comprising an electrical conductor whose resistance per turn decreases as its voltage increases, and an exciting field winding adjacent to and confined to the low-voltage portion of said conductor, substantially as described.
That. In an induction apparatus, a plurality of turns of electrical conductor, said conductor being constructed and wound to exhibit a decrease in resistance in turns towards one end with an increase in voltage towards the same end when under the influence of current, and means for maintaining said high voltage at said end of minimum resistance per turn, substantially as described.
5. An induction device having a sheet metal primary, the turns of said primary being insulated from one another by a saw cut, substantially as described.
6. An induction device comprising a shallow box having a closed bottom and an intermediate partition, said partition extending to the walls of the box parallel to the bottom, a flat coil of a single thickness of wire being contained between the partition and the bottom of the box and confined to that portion of the box adjacent to the box walls, and a flat coil constituting a secondary contained in the box on the opposite side of said partition and extending approximately to the center of the box. case, the case is filled with said primary and secondary being embedded in a normally solid fusible insulating substance, substantially as described.
7. An induction device comprising a shallow box having a closed bottom and an intermediate partition, said partition extending to the walls of the box parallel to the bottom, a flat coil of a single thickness of wire being contained between the partition and the bottom of the box and confined to that part of the box adjacent to the box walls, and a flat coil constituting a secondary contained in the box on the opposite side of said partition and extending approximately to the center of the box, the case is filled with, and said primary and secondary being embedded in a normally solid fusible insulating substance, said secondary being retained from distortion by means of an insulating grid comprising bars extending through it both above and below. bottom,substantially as described.
S. An induction apparatus comprising a plurality of primaries connected in series at one of its terminals, combined with a secondary for each primary, said primaries and secondaries being constructed and arranged to maintain high voltage at the center of each secondary, and low voltage at its circumferential terminals, the inner terminal of one of said secondaries being positive and the inner terminal of the adjacent secondary being negative, substantially as described.
9. An induction apparatus comprising a plurality of primaries connected in series at one of its terminals, combined with a separate secondary for each primary, said secondaries having high-voltage regions at their centers and low-voltage regions at their circumferential terminals when the apparatus is in action, substantially as described.
10. An induction apparatus comprising a plurality of primaries connected to each other, and a secondary for each primary, said secondaries being respectively located substantially coaxial with respect to their primaries, and each one being wholly or mainly within the primary, the latter being adjacent to the circumferential portion. of the secondary only, where by means of a large propelling discharge it can be maintained in the central terminal of the secondary with a negligible discharge in the circumferential terminal thereof, substantially as described.
1l. An induction apparatus comprising an IOO IIO
a plurality of thick, short and flat primary coils connected together, and a corresponding plurality of long and thin secondary coils wound in the form of flat coils, each primary coil being wound with a large central opening and having its coils restricted to the area adjacent to the longer of the gyrations of its secondary, substantially as described.
l2. An induction apparatus comprising a shallow case having a plurality of compartments and removable covers therefor, each compartment containing one coil constituting a primary coil and a second coil constituting a secondary coil, said coils being coaxial with each other and the secondary extends within the primary, said coil the coils are embedded in a normally solid fusible insulating substance and fills said various compartments, said box has insulated passages connecting said boxes, and said various primaries have one of its terminals communicating to through said passages7 and a rear discharge device for the central terminal of each secondary one, substantially as described.
13. An induction device comprising a 10 W box having a closed bottom, a flat coil of a single thickness of wire adjacent to said bottom and confined to the walls of the box, and a flat coil constituting a winding. child contained in the adjacent box. the other winding and extending approximately to the center of the case, said secondary winding being retained from being deformed by means of a plurality of glass bars arranged transversely thereto on opposite sides of the winding, the case being filled and said primary and secondary being embedded in a normally solid gsubst-ance fusible insulator, substantially as described.
14C. An insulating grid adapted to join and insulate a disk or other winding, said grid being composed of glass bars arranged opposite each other on opposite sides of the winding and protruding from it at their ends, said ends having heads adapted to be joined by a wail, substantially as described.
In witness whereof, I have signed my name on this specification in the presence of two signing witnesses.
THOMAS B. KINRAIDE. Witnesses:
GEO. H. MAXWELL, ALEXANDER C. PROUDFIT.