US1845406A

US1845406A - Inductance system

Info

Publication number: US1845406A
Application number: US416158A
Authority: US
Inventors: Louis A Gebhard
Original assignee: Wired Radio Inc
Current assignee: Wired Radio Inc
Priority date: 1929-12-23
Filing date: 1929-12-23
Publication date: 1932-02-16
Anticipated expiration: 1949-02-16

Description

INVENTOR. v

3 SheetsfSheet 1 SGM/io,

L. A. GEBHARD INDUGTANCE SYSTEM Flled Dec 23 1929 Feb. 16,V 1932.

' Feb. 16, 1932.

L. Af GEBHARy v 1,845,406

INDUGTANCE SYSTEM 5 Sheets-Sheet 2 Filed Dec. 25, 1929 INVENTOR. (y comenagw,

TTORNEY Feb. 16, 1932. L. A. GEBHARb 1,345,406

INDUCTANCE SYSTEM F'iled Dec. 23, -1929 '3 Sheets-,Sheet 3 INVEN TOR. A.

TTORNEY Parma-d Feb. 16, 1932 UNITED STATES PATENT OFFICE LOUIS AQGEBHARD, OF WASHINGTON, DISTRICT OE COLUMBIA, ASSIGNOR TO WIRED RADIO, INC., OF NEW YORK, N. Y., A CORPORATION OF DELAWARE INDUCTANCE SYSTEM Application led December v23, 1929. Serial No. 416,158.

My invention relates broadly to high frequency inductance systems and more particularly to a construction of coupling 1nductance for high frequency signal transmission systems.

One of the objects of my invention is to provide a mechanical system for adjusting the effective number of turns of inductance in a signal transmission circuit and controlling the coupling of the transmission circuit with respect to the radiation system.

Another object of my invention is to provide a construction of inductance system which may be readily adjusted to predetermined positions for fixing the effective inductance in the transmission circuit and the coupling of the transmission circuit with respect to the radiation system.

A further object of my invention is to provide a construction of adjustable inductance system by which a maximum value of inductance may be connected in the transmitter circuit and the coupling varied with respect to the radiation circuit by mechanical means variable with respect to each other along the inductance in such manner that the effective inductance may be varied throughout the entire length thereof for tuning the transmitter circuit while a minor portion of the inductance may be effectively selected for connection in the radiation circuit for varying the coupling between the transmission circuit andthe radiation circuit.

Still another object of my invention resides in the construction of a variable inductance system having means for predetermining the position of a pair of variable contactors along a helical `inductance and selectively setting the contactors in desired positions for fixing the frequency and coupling adjustment of a signal transmission system.

A stillfurther object of my invention is t0 provide -a'construction of fluid cooled high frequency inductance system having means Lfor variably including an effective number of turns of inductance in the transmitter circuit and a smaller number of turns in a coupling circuit for coupling to a radiation system while maintaining all of the turns of the inductance at a predetermined temperature by means of a Hind circulation system.

Other and further objects of my invention reside in the construction of high frequency inductance system set forth more fully in the specification hereinafter following by reference to the accompanying drawings, in which:

Figure l shows a lateral cross-sectional View taken through a transmitter panel and illustrating the arrangement of high frequency inductance system of my invention with parts thereof shown partially in crosssection and partially in elevation; Fig. 2 shows a side elevation of the inductance system of my invention; Fig. 3 is a rear view of the inductance system looking in the direction of arrow A in Figure 1; Fig. 4 is an enlarged cross-sectional view taken through one turn of the inductance adjacent one end thereof and showing the cooling fluid connection thereto; Fig. 5 is a cross-sectional View taken through the end support of the rotatable adjusting means for controlling the effective number of turns of the inductance in the transmitter circuit and the ycoupling of the transmitter circuit with respect to the radiation circuit; and Fig. 6'is a diagrammatic View showing the wiring arrangement of the transmitter circuit and radiation system embodying the principles of my invention.

. 'In high frequency transmission systems employing screen grid tubes, it is desirable to have the output circuit contain as much inductance as possible at the particular frequency of operation. This 1s particularly desirable for efcient operationat high frequencies and may be accomplished by having the inductance coil in the electron tube system at the transmitter arranged so that the effective inductance is continuously variable throughout the length thereof by means of a. slider which passes over all of the turns of the coil. It is also desirable t0 piovide another v adjustable slider on the inductance to effect a continuously variable coupling or other adjustment. The coupling adjustment slider may be located at .a point along the induc-` tance which provides a lower effective induct-ance than is required by the slider which is used for the tuning adjustment. This arrangement permits a system to be employed in which the sliders do not pass each other but where the sliders may be progressively changed in position throughout the length of the inductance. The inductance system of a high frequency transmitter should be maintained at constant temperature for securing maximum eiiiciency in operation, and vthe frequency change and variable coupling system of my invention is designed to permit change in the effective inductance and effective coupling' between the transmitter circuit and radiation system while maintaining the inductance elements at constant temperature.

Referring to the drawings in more detail, reference character 1 designates the inductance coil which is in the form of a fiat tubular member having the turns thereof located A substantially in vertical planes and supported in helical formation by means of insulated laterally extending spacer members 2 which are supported at opposite ends by means ofend plates 3 and 4. Screws 5 pass through end plates 3 and 4 securing the inductance in position with respect to the insulated frame. The end plate 4 has a bearing plate 6 secured adjacent the center thereof in which rotatable shaft 7 is journaled for rotary movement.'

The shaft 7 is in the form of a hollow conductive tube which encloses the screw 8 which is secured to the insulating member 9. The

u slider 10 is actuated by the rotation of shaft 7.under control of crank 14. The shaft 7 contains a longitudinally extending slot 7 a through which screw 11 carried in slider 10 projects. The inner end of screw 11 engages the screw threads in the screw 8 which threads are cut to correspond to the pitch of the turns of the inductance coil 1. The rotation of shaft 7 causes turning of slider 10 which moves along the coil 1 in accordance with the position of the turns. The slider 10 carries l brush members 12 which engage opposite sides of the turns of flattened tubular inductance 1. In order to impart rotative movement to shaft 7, I provide the crank 14 operative from the front of the control panel 17, which crank is insulated from shaft 7 by means of insulating member 13. Rotative movement of the crank 14 imparts corresponding movement to the beveled gears 15 operating a counter 16 which is visible from the front of the control panel 17 of the transmitter thereby permitting resetting ofthe slider to any selected point along the coil. The counter 16 is mounted upon plate 17 awhich is supported by insulating members 18 from the end plate 4. A second s1ider-19 constituted by brushes engaging opposite sides of the turns of flattened tubular inductance 1 is arranged to control the coupling between the transmitter circuit and the associated radiating circuit. Slider 19 is mounted on rod 20 which slides longitudinally into tube 21. In order to prevent loss motion or displacement of the rod 20, the tube 21 is made square-in cross-section to receive theA rod 20 which is square in cross-section. The tube 21 is secured to arm 22 which is connected with beveled'gear 23 as shown more clearly in Fig. 5. A brace 24 extends between one end of arm 22 and the extremity of the tube 21 thereby rigidly strengthening the movable assembly. The arm 22, brace 24 and gear 23 are secured together by means of pins 25 or the parts may be sweated or otherwise connected for forming an assembly rotatable in unison. The assembled group of

parts

22, 23 and 24 are arranged to revolve about shaft 26 which is rigidly secured in `support 27 by means of pin 28. The support 27 is carried by the insulating

members

41 and 42 which are supported from the base 40 by a suitable bracket or other means. In order to impart movement to gear 23, arm 22 and brace 24, I provide/

resilient washer members

29 and 30 which serve as spacer means on each side of the assembled sets of parts 23. 22 and 24, permitting easy turning of gear 23 under control of gear 31 actuated by rotative movement of the beveled gears 35 through shaft 32 and insulating connecting. member 34 which interconnects the gear system 35 with the gear system 31-123. The insulating member 9 which is fixed to the threaded rod 8 is connected by screw threaded portion 30a of shaft 26 with the rigid shaft 26 so that central rod 8 is maintained stationary while the hollow tubular shaft 7 revolves over the screw threaded rod 8 as an envelope.` In order to insure a tight connection between insulated rod 9 and shaft 26, I apply a suitable locking cement for binding the screw threads 30a of the insertable shaft 26 with respect to the socket portion of insulating member 9. The shaft 32 which interconnects beveled gears 35 and 31 is journaled at one end in bracket 33 and at the other end in bracket 43. The beveled gear 35 is intermeshed with a correspondingly positioned beveled gear which is operated by shaft 36 and crank 37 from the front of the panel 17. `The beveled gears 38 which are operated in accordance with the rotation of shaft 36 under control of crank 37 connect with the counter 39 and enable readings to be taken from the front of panel 17 for predetermining the position o ff the slider 19 with respect to the inductance 1. The counter 39 ismounted upon the plate -17 a in a manner similar to counter 16. The end plate 3 is apertured adjacent its center as shown in Fig. 3 to permit the revolving of the parts 21. 22 and 24 through 360 degrees or some multiple thereof for moving the slider 19 over predetermined bushing 6a associated therewith, and collar 45 with the hollow tubular shaft 7. The connection to the slider 12 is completed through the split brush 46 which engages the surface of the hollow tubular shaft 7, through slider 10, flexible spring 47, and to the parts of slider 12 which wipes opposite sides of each of the turns of the fiat tubular inductance 1. The connection to 'brush 19 is made through binding post 48, bearing block 27, shaft 26. arm 22, tubular member 21, brush device 49, and rod 20. The brush 49 maintains a frictional grip upon rod 2O as the rod is adjusted Witl respect to the tubular supporting member 21. The

resilient washer members

29 and 30 are of the disc shaped spring type having radial slots to provide a good connection between the bearing support 27 and the revolving group of

parts

23, 22 and 24.

The inductance system is maintained in' permanent position and cooling fiuid supplied to the hollow tubular inductance as illustrated. The inductance 1 has flattened side walls 50 providing a narrow fluid. circulating path indicated at 52. The iattened tube is wound edgewise with respect to the laterally extending frame member 2. The cooling fluid enters one end of the coil, passes through the coil, and discharges from the other end thereof. The fluid connection for the entrance and discharge of the fluid is shown more clearly in Fig. 4. The exterior of the tubular inductance member is indicated at 51 and the hollow interior thereof shown at 52 with the end plugged as indicated at 53 which prevents the cooling fluid from fiowing out of the end of the tube. Into the side or edge of the tubular conductor 51, l provide the tube 54 which is sweated therein to provide communication with the interior fluid passage 52. Over the tube 54 there is placed an insulating tubing 55 which serves to complete the path for the coolv ing fiuid to or from the inductance per se, and at the same time serves to insulate the ends of the inductance from the remainder of the cooling fluid circuit. Clamps 56 are provided to hold the insulating tubing on to the tubing 54. this construction the inductance is 'formed of a relatively fiat tubular envelope closed at each end and into the sides of the envelope adjacent each end thereof, there is admitted or delivered therefrom a suitable cooling Huid.

Figure 6 diagrammatically illustratesthe connect-ion of the inductance system 'of my invention between the output circuit of a screen grid power amplifier circuit and a radiation system. The last stageof power amplification is shown'as including a screen grid tube 60 in theoutput circuit of which the fluid cooled inductance system 1 is connected. The'slider 12 connects to the plate electrode of the electron tube system and one end of the inductance connects to the other end of the output system of electron tube 60.

Proper tuning capacity indicated at 57 may be introduced across a selected number of turns of inductance by means of switch 58. The radiation system is shown as including an antenna 61 and ground 62 in series with tuning inductance 63. The slider 19 connects through condenser 64 with the radiation circuit and by adjustment of slider 19 along inductance 1 the coupling between the output system of electron tube and the radiation efficiency in high frequency signal transmission, and while I have described a certain preferred embodiment of my invention, I desire that it be understood that modifications may be made and that no limitations are intended other than those imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is as follows:

l. A high frequency inductance system comprising an insulated frame structure, a fluid cooled inductance spirally positioned within said insulated frame structure, a central shaft extending through said frame structure, said shaft being divided into two conductive portions insulated from each other, a pair of brush contact members concentrically related to said central shaft and respectively supported by portions of said shaft which are insulated from each other and independent means for adjusting said brush contact members along said inductance from opposite ends thereof toward the center.

2. In a high frequency inductance system, an insulated frame structure, an inductance spirally positioned within said insulated frame structure, a central shaft eXtendng through said framestructure, said shaft being divided into two conductive portions insulated one from the other, abrush engaging the turns of said inductance and operative under control of Vvrotary movement of said central shaft, an independent brush engageable with the turns of said inductance, said brushes being respectively supported by portions* of said shaft which are insulated from each other, and means for advancing said independent brush along said inductance from the end thereof toward the center, said means operating independently of the rotary movement of said shaft.

3. In a high frequency inductance system,

an insulated frame structure, a spirally positioned fluid cooled inductance mounted within said frame structure, a` shaft member extending through said frame structure, said shaft'member being divided into a pair of separate portions insulated one from the other, a contact device engaging the turns of said inductance and shiftable under control of said shaft member, an independent contact device engageable with said inductance, said contact devices being respectively rotatably supported by portions of said shaft which are insulated. from each other, and

i separate controls for imparting independent movement to each of said contact devices.

4. In a high frequency inductance system comprising an insulated frame structure, a fluid cooled inductance spirally positioned within said insulated frame structure, a central shaft extending through said inductance, means dividing said shaft into a pluralityof portions insulated one from the other, a brush contact device engaging the turns of said inductance and shiftable in position with respect thereto under control of one portion of said shaft, an independent brush contact device centered with respect to the other portion of said shaft, and means for driving said independent brush contact device around said shaft for engaging the turns of said inductance independently of the rotation of said shaft and independently of the movement of said first mentioned brush contact device.

5. In a high frequency inductance system, an insulated frame structure, a fluid cooled inductance spirally mounted Within said insulated frame structure, a rotary shaft journaled centrally with respect to said insulated frame structure, said shaft being divided into two portions with an insulating connector therebetween, a contact devicer engageable i with the turns of said inductance and adapted to be rotatedV around one portion of said shaft, a separate contact device engaging the turns of said inductance and controllable by the rotative movement of the other portion of said shaft, and means for independently inductance spirally mounted within said frame structure, a shaft member extending centrally through said inductance, said shaft member including an insulating connector Y dividing said shaft member into two independent portions, a brush Contact device engageable with the turns of said inductance and shiftable along said in ductance in accordance with the rotation of said shaft, an independent brush contact device arranged to engage the turns of said inductance, a carrier concentrically positioned with respect to the other portion of said shaft and having sliday ble connection with said independent brush contact device, and means, for imparting rotary movement to said carrier independently of the rotary movement of said shaft for adjusting each of said Contact devices along said inductance. l

7. A high frequency inductance system comprising an insulated frame structure, an inductance spirally positioned within said insulated frame structure, a rotary shaft extending through said inductance, said shaft being divided into a pair ofindependent p0rtions insulated one from the other, a contact device engaging the turns of said inductance and controllable in position along said inductance bythe rotatable adjustment of one portion of said shaft, a separate contact device engageable with the turns of said inductance, a rotatable carrier concentrically positioned with respect to the other portion of said shaft, slidable connecting means interposed between said carrier and said separate ncontact device, and means for imparting rotary movement to said carrier independently of the rotary movement imparted to said shaft for effecting an adjustment of eachy of said contact devices along said inductance.

8. vIn a high frequency inductance system, a helical tubular'inductance member, a shaft disposed in the axis of said helical member,

said, shaft being divided into two portions insulated from each other, a contact member engaging the turns -of said inductance member, means for moving said contact member along said inductance member under control of one portion of said shaft, an independent contact member engaging the turns of said inductance member, means for moving said independent contact member along said in ductance member under the control of the other portion of said shaft, a fluid inlet member attached to said 'tubular inductance member at one end thereof and communicating with the interior-thereof, and a fluid outlet member attached to said tubular inductance member at the opposite end thereof and communicating With theinterior thereof, whereby cooling fluid is delivered to one end of said tubular inductance member and flows' through the entire length of said member to the opposite end thereof.

9. In a high frequency inductance system, a helical tubular inductance member, a shaft disposed `in the axis of said helical member, saidshaft being divided into two portions insulated lfrom each other, a contact contact member along said induct-ance member under the control of the other portion of said shaft, a fluid inlet member attached to said tubular inductance member at one end thereof and communicating with the interior thereof, and a iuid outlet member attached to said tubular inductance member at the opposite en d thereof and communicatin with the interior thereof, whereby cooling uid is delivered to one end of said tubular inductance member and flows through the entire len h of said member to the opposite end thereo 10. In a high frequency inductance System, a helical tubular inductance member, a shaft disposed in the axis of said helical member, said shaft being divided into two portions insulated from each other, a contact member engaging the turns of said inductance member', means for moving said Contact member along substantially the entire length of said inductance member under control of one portion of said shaft, an independent contact member engaging the turnsA of said inductance member, means for moving said independent contact member along said inductance member under the control of the other portion of said shaft, a fluid inlet member attached to said tubular inductance member at one end thereof and communicating with the interior thereof, and a fluid outlet member attached to said tubular inductance member at the opposite end thereof and communicating With the interior thereof, Wherev by cooling fluid is delivered to one end of said tubular inductance member and flows through the entire length of said member to the opposite end thereof.

LOUIS A. GEBHARD.