US2113005A - Mount for electron discharge devices - Google Patents

Description

N. R. SMITH MOUNT Eon ELECTRON DISCHARGE DEVICES Fiied July 31, 1936 INVENTOR NEWELL R. SMITH '&4MW

TTORNEY Patented Apr. s, 1938 UNITED STATES MOUNT FOR ELECTRON DISCHARGE DEVICES Newell R. Smith, Bloomfield, N. J., assignor, by mesne assignments, to Radio Corporation of America, a corporation of Delaware Application July 31, 1936, Serial No. 93,534

7 Claims.

devices employing two or more independent electrode assemblies in one envelope.

5 The conventional multi-unit radio tube comprises one self contained electrode assembly, or section, usually of the unit mount type of con struction, supported upon the upper end of longi tudinal' support rods rising from the stem and 10 with another electrode assembly or section at the lower end of the envelope supported directly on the stem. The electrodes and shields of the lower section which usually are individually supported upon lead-in wires extending through the press 1 5 are diflicult to assemble and to maintain in fixed spaced relation.

According to my invention the elements of the lower section, which may for convenience be referred to as a double diode, is constructed as a unitary assembly of electrodes and shielding means. A box-like shield receives the electrodes and insulating spacers and is adapted to be easily and economically assembled in the mount.

My invention is defined with particularity in the appended claims, but one embodiment thereof is described in detail in the following specification and accompanying drawing in which:

Figure 1 is a front elevation, partially in section, of an electron discharge device embodying 30 my invention, and

Figure 2 is an exploded perspective View, partly in section, of a double diode assembly embodying my invention.

The mount assembly shown in Figure 1, which 35 is particularly adapted for a metal envelope, comprises a stem or metal header I with electrode lead-in wires 2 sealed gas tight in glass beads in eyelets 3. The upper electrode assembly comprises insulating spacers and 5 which support 40 between them the cooperating cathode 6, grid 1 and anode 8, and which are mounted upon support rods 9 joined at their lower ends to the header. In this tube the cathode of the indirectly heated type extends below lower spacer 5 and is .15 coated at ID with electron emitting material for supplying space current to an assembly of electrodes constructed and supported in accordance with my invention.

An assembly of diode plates adapted to cooper ate with electron emitting surface l0 and better shown in the exploded view of Figure 2 comprises a box-like shield 20 which may as desired be either open or closed on its sides is preferably of nickel, and has an indented or recessed por- 55 tion 2|, which serves to space the top of the (o1. cam-27.5)

My invention relates to mounts for electron discharge devices, particularly to multi-purpose' shield from the lower ends of the electrode side rods of the upper section. A rectangular insulating plate or spacer 22 bears snugly in the upper portion of the shield against recessed portion 2| and insulating plate or spacer 23, slightly longer in one dimension than the shield, is attached 'to the lower edge thereof by ear extensions 24 from the box. In the bottom of recess 2| and in lower spacer 23,are registering openings 25 and 26 to receive the lower end of the cathode with emitting surface l0. 'I'wo coaxial tubular anodes 21 and 28 are each positioned concentric with emitting surface l0 and held upon two pairs of support rods 29 and 30 between the insulating spacers. For convenient attachment to the support rods the anodes may have integral extensions 3| and 32, notched to provide offset portions so the extensions of one anode may if desired lie in one plane and at an angle to the plane of the other anode extensions and be attached to diagonally opposite support rods. To longitudinally space the two coaxial anodes, each extension may conveniently be of a width at its end adjacent the support rods slightly greater than the total length of the two coaxial anodes. Each anode is thus securely held in place upon two opposed support rods which are held in fixed spaced relation to the cathode and to the sides of the box shield. Each anode is connected through one of its support rods to a lead-in wire of the header. This assembly of anodes is not only rugged in construction but is easily manufactured and assembled with the upper section -of the mount. In assembling the mount, the shield containing the diode anodes and their insulating spacers, is attached to support rods 9 near the stem, preferably by welding opposite faces or extensions from the faces of the shield to the rods, and the upper assembly of electrodes is then added by threading rods 9 through holes in 40 insulating spacers 4 and 5 and inserting cathode 6 the proper distance to bring emitting surface I0 in registry with the diode anodes, the lower spacer 5 coming into fiat engagement with the upper face of the shield. In addition to ruggedness-and simplicity of manufacture the electrode assemblies constructed in accordance with my invention are eflectively shielded electrostatically, and electronically to reduce interaction between the two sections of the mount. Since many modifications may be made in an electrode assembly constructed according to my invention without departing from the scope thereof, it is desired that my invention be limited only by the prior art and by the appended claims.

I claim:

1. In combination in an electron discharge device, an envelope. a stem closing one end of said envelope, parallel support rods attached to and projecting from said stem into said envelope, a box-like shield with opposite ends secured to said rods and having an opening in the top, an electrode assembly resting on the top of said shield and secured to said rods, said assembly having a cathode with its lower end pro] ecting through said opening into said shield, and a tubular anode in said shield concentric with the lower end of said cathode, said anode having radial extensions, said extensions being insulatingly secured to the top and bottom of said box.

2. An electron discharge device comprising a stem, two support rods projecting from the stem, 9. box-like shield secured to said support rods near the stem and having an opening in its top, an electrode assembly mounted on said support rods and comprising a spacer resting on the top of said shield, and a cathode with an electron emitting surface projecting into said box through said opening, spaced insulating discs held in said shield, a tubular anode in said shield concentric with said emitting surface of the cathode, and means for securing said anode to said insulating discs.

3. An electron discharge device comprising in combination a stem, parallel support rods projecting from the stem,'a rectangular sheet metal box with its ends secured to said support rods and having an opening in the top, an electrode assembly attached to said support rods and resting on the platform formed by the top of said box and comprising a cathode with and an emitting surface projecting into said box through said opening, an anode in said box concentric with said electron emitting surface of the oathode, said anode having extensions insulatingly secured to the walls of said box.

4. A multi-unit mount for electron discharge devices comprising a stem and two upstanding support rods, two transversely spaced electrode spacers attached to said support rods, a cathode extending between said spacers and below the lower spacer, a rectangular box-like shield attached at opposite ends to said support rods and bearing at its upper side against said lower spacer, two insulating discs in said shield transverse to said rods, two anodes surrounding the lower end of said cathode and secured in spaced relation to said insulating discs.

5. An electrode assembly comprising a metal box-like shield, two insulating spacers at opposite sides of said shield, a cathode between said spacers, two tubular coaxial anodes surrounding the cathode between the spacers and each having two radial extensions, each extension being as wide at the ends as the distance between said spacers, and means for securing said extensions to said spacers, the'plane oi the extensions of one anode being at an angle to the plane of the extensions of the other anode.

6. In combination in an electron discharge device, a rectangular metal box, two insulating plates secured to opposite sides of said box, registering openings in said plates and the sides oi said box, a cathode extending between and titted in said openings, two coaxial anodes held in spaced concentric relation around said cathode between said plates, and two pairs of side rods, each rod being parallel to said cathode and engaging said plates at its ends and spaced around said openings, each anode being secured to alterhate rods.

7. In an electron discharge device having in combination a rectangular metal box, two insulating plates secured to opposite sides of said .box, registering openings in said plates and the sides of said box, a cathode fitted in said openings, two coaxial anodes held in spaced concentric relation around said cathode between said plates, and two'pairs of fastening means for securing each anode to said plates at spaced points aroundsaid openings, each anode being secured to alternate fastening means.

NEWELL R. SMITH.

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