US2917812A - Apparatus for assembling an electrode cage for electron discharge devices - Google Patents

Description

Dec. 22, 1959 WQLKE ET AL 2,917,812

ASSEMBLING AN ELECTRODE CAGE FOR ELECTRON DISCHARGE DEVICES Original Filed May 26, 1951 APPARATUS FOR 2 Sheets-Sheet '1 K WOLKE ET AL 2,917,812

FOR

R. APPARATUS FOR ASSEM L NG ELECTR CAGE SCH E DEVIG Dec. 22, 1959 w ELECTRON Original Filed May 26, 1951 2 Sheets-Sheet 2 2,917,812 Patented Dec. 22, 1959 APPARATUS FOR ASSEMBLING AN ELECTRODE CAGE FOR ELECTRON DISCHARGE DEVICES Roy Karel Wollie, Mapiewood, John Anthony Chase, Nutiey, and Frank 5. Piias, Lyndhurst, N.J., assignors to Radio Corporation of America, a corporation of Delaware Original application May 26, 1951, Serial No. 228,386, now Patent No. 2,778,968, dated January 22, 1957. Divided and this application April 26, 1956, Serial No. 580,952

1 Claim. (Cl. 2925.19)

The present invention relates to apparatus for and a method of assembling the components of an electrode cage.

This is a division of application of F. J. Pilas, R. K. Wolke, and J. A. Chase, Serial No. 228,386, filed May 26, 1951, now Patent No. 2,778,968, issued Jan. 22, 1957, and assigned to the same assignee as the present application.

Conventional electrode cage assemblies for electron tubes include a cathode and one or more other electrodes mounted between a pair of insulating spacer members or plates. A serious problem has heretofore characterized such cage assemblies.

This problem involves the mounting of the electrodes on the spacer plates. The mounting of the electrodes on the spacer plates usually involves extending end portions of the electrodes thru suitable apertures provided in the plates. While it is desirable to have as close a spacing as possible between the electrode end portions and the walls of the apertures in the spacer plates for good support, such close spacing introduces difficulties in extending the electrode end portions into the apertures, particularly when the end portions referred to are relatively fragile and the material of the spacer plate is not flexible and therefore likely to disintegrate in response to a forced entry.

Accordingly, it is an important object of the invention to provide an improved jig and method for facilitating the mounting of an electrode on an insulating spacer plate.

A further object is to provide an improved jig for mounting parts to form an electrode cage with reduced damage to said parts.

Briefly considered, there is provided according to the invention a novel jig and method which contribute to an improved electron tube cage. 7

The jig and method of the invention are particularly advantageous in connection with assembling parts to form an electrode cage, where one of the parts comprises a spacer plate having apertures for receiving end portions of electrodes and a plurality of slots communicating with each aperture and forming flexible segments therearound.

According to one aspect of the invention, the flexible segments referred to when engaged by an electrode entering an aperture, are deflected in the direction of electrode travel to form a funnel for aiding the entrance of the electrode into the aperture with reduced harm to both the spacer plate and the electrode.

According to another aspect of the invention, a novel jig is provided having fingers disposed in a closed array and adapted to enter the slots referred to and to supplement the function of the segments in defining edges of an aperture. The fin gers are tapered toward their free ends inwardly of the closed array referred to, so that they form an effective funnel for directing an electrode end portion into the aperture mentioned, l

Further objects and advantages of the invention will become manifest as the present description proceeds.

Referring now to the drawing for a better understanding of the invention,

Figure 1 shows an exploded elevation of parts included in the electrode cage of one type of electron discharge device;

Figure 2 is a side view of an electrode cage assembled from the parts shown in Figure 1;

Figure 3 is a plan view of an insulating spacer plate that may be used in the cage shown in Figure 2;

Figure 4 is a sectional elevation of a jig that may be used according to one aspect of the invention in mounting the parts shown in Figure 1 to form a cage;

Figure 5 is a sectional elevation of a jig according to another aspect of the invention that may be used advantageously in forming a cage from the parts shown in Fig. 1;

Figure 6 is an enlarged partly sectional view along the line 6-6 of Figure 5 and shows one group of funnelling fingers of the jig in relation to the structure of a spacer plate and electrode;

Figure 7 is an enlarged partly sectioned view along the line 77 of Figure 5 and shows another group of funnelling fingers of the jig; and

Figure 8 is a plan view of an electrode cage including a cathode, a grid and an anode assembled by the use of the novel jig and method of the invention.

Referring now to the drawing in more detail, there is shown in Figure 1 thereof, components of one type of electrode cage in connection with which the jig and method of the invention find particular utility. The parts referred to comprise a cathode sleeve 10, an anode 11 having side wings 12, 13 defining passageways for receiving anode support rods 14, 15. The cathode sleeve and anode referred to are supported between spacer plates 16, 17 which have apertures for receiving end portions of the cathode sleeve and the anode support rods. The electrode cage formed of these parts is shown in Figure 2 and is adapted to be used in a diode type of electron tube.

One or both of the spacer plates 16, 17, which may be made of an insulating material such as mica, are provided with tongues or segments defining slots and electrode-re ceiving' apertures or passageways as shown in Figure 3. The aperture 18 is adapted to receive cathode sleeve 10 and the apertures 19, 20 are adapted to receive the anode support rods 14, 15.

The aperture 18 is defined by segments 21, 22, 23, 24. The segments referred to also define slots 25, 26, 27, 28. The segments constitute tongues integral with the spacer plate and flexible by bending along straight lines indicated by dotted lines, in response to the force exerted on the tongues by a cathode sleeve entering the aperture 18.

Each of the apertures 19, 20 for receiving anode support rods 14, 15 is defined by segments 29, 30, 31, 32. Slots 3.3, :34, 35, 36 communicating with the apertures 19, 28 are also defined by the segments referred to. The segments mentioned are integral with the spacer plate and are flexible along straight lines shown by dotted lines in response to the thrust thereon of anode support rods 14, 15, when the same are extended into apertures 19, 20.

According to one aspect of the method of the invention, the flexure of the segments or tongues defining the apertures 18, 19 and 20, causes them to assume a position in which they form a partial funnel. This partial funnel not only guides electrode end portions into the apertures referred to but also serves to widen the aper tures.

For mounting the electrodes referred to on a spacer plate according to the presently discussed method aspect of the invention, use may be made of a novel mounting jig 37' shown in Figure 4. The upper surface of the 3 jig is provided with cavities S8, 39, 40 defined by edges adapted to be disposed in substantial registry with the dotted lines along which the segments or tongues defining the apertures'18,'19, 20 flex, as shown in Figure 3. The jig includes two locating lugs, one of which is shown at 41 in Figure 4, for engaging apertures 42, 43 shown in Figure 3 to properly register the dotted line portions of the piate with the edges of cavities 38, 39, 40. The bottoms 44, 45, 46 of the cavities referred to serve as stops for the electrode end portions to be extended into the apertures 18, 19, 20. The bottoms of cavities 38 and 49 are lower than the bottom of cavity 39 to permit adjacent ends of the anode support rods 14, 15 to extend farther from the plate 16 than the adjacent end of the catho'de sleeve 10. The jig is also provided with a mandrel 47 on which the cathode sleeve is adapted to be threaded for registry with the aperture 18 in the spacer plate. The bottom 45 of cavity 39 may be raised or lowered by movement of shaft 48, the upper surface of which forms the cavity bottom 45. The shaft 48 may be locked in desired position by lock screw 49.

As shown in Figure 4, when the anode support rods 14, and the cathode sleeve 10 is urged into apertures 18, 19, of the spacer plate 16, the segments defining the apertures flex to form a funnel-like structure. If any of the electrodes is improperly registered with any of the appropriate apertures referred to, it is urged into such registry by the sloping surfaces of the segments forming the funnel-like structure. This facilitates a mounting operation and renders automatic mounting procedures practicable. It also makes feasible a continuing engagement between the electrodes and the spacer plate resulting from a force exerted by the flexed segments on the electrodes. This last mentioned advantage requires that the apertures 18, 19, 20 in the spacer plate be slightly smaller than a cross-section of the electrode portions received therein.

According to another aspect of the invention a mounting operation is provided during which the segments defining the apertures 18, 19, 20 therein are not flexed. A novel jig 50 for use in this type of operation is shown in Figure 5. This jig is similar in some respects to jig 37 shown in Figure 4. For example, it has cavities 51, 52, 53 in its upper surface, the cavities having bottoms 54, 55, 56 serving as stops for electrodes to be mounted. The bottom 55 is formed by the upper end surface of cathode.

an adjustable shaft 57 and the shaft referred to is fixed after adjustment by lock screw 58.

However, jig differs from jig 37, in that the cavities 51, 52, 53 therein have transverse dimensions substantially equal to the cross-sections of end portions of electrodes to be received therein. The edges of the cavities are not therefore in registry with the dotted lines shown on the spacer plate in Figure 3.

To facilitate extension of the electrodes into the apertures 18, 19, 20 in the spacer plate, without flexing the segments thereof, the jig 56 is provided with a plurality of fingers or risers 59, 60, 61, 62 around cavity 52 as shown in Figure 6, having bevelled sides 63, 64, 65, 66 for forming a funneHike structure for guiding cathode sleeve 10 into aperture 18 in the spacer plate. Around each of the cavities 54, 56 are also disposed a plural ty of risers 6'7, 68, 69, 70 as shown in Figure 7, having bevelled sides 71, 72, 73, 74 forming funnel-like structures for guiding the anode side rods 14, 15 into apertures 19, 20 in the spacer plate.

The slots in the spacer plate render the advantageous jig shown in Figure 5 feasible. The slots 25, 26, 27 and 28 in the spacer plate permit extension of the risers in the jig through the plate, to provide the funnel-like structure referred to for guiding the cathode sleeve 10 into aperture 18. The slots 33, 34, 35, 36 adjacent each of the apertures 19, 20 in like manner permit extension through the plate of risers 67, 68, 69, 70 for guiding the anodes side rods 14, 15 into apertures 19, 20.

Each of the mounting modes shown in Figures 4 and 5 has distinct advantages. For example, when the spacer plate is made of flexible material such as mica, the mounting procedure shown in Figure 4 has particular advantages in that it both provides a guide for the electrodes into the spacer apertures, and also assures a subsequent firm engagement between the spacer plate and the electrodes. However, where the spacer plate is made of a material such as ceramic that is incapable of flexure without breaking, the novel and advantageous jig of Figure 5 is of particular usefulness for guiding the electrodes into the apertures in the spacer plate.

It will be observed that while the slots 26, 28 are utilized in the mounting procedure shown in Figure 5, the slots 75, 76 are necessary for disposing the risers 59, 61 adjacent the path followed by a cathode sleeve during a mounting operation. If leakage slots 26, 28 were isolated from cathode aperture 18, as in the prior art, the advantageous operation permitted by jig 50 could not be carried out. I While the foregoing description has'concerned spacer plate 16, it will be understood that spacer plate 17 shown in Figure 2 may be of similar construction. Thus, the mounting procedures shown in Figures 4 and 5 may be employed for first mounting the electrodes on one plate, and then mounting them on the second plate.

It will be noted that the segments 21, 22, 23, 24 shown in Figure 3, are formed so that each segment has one set of opposite and parallel edges. This results in a segment having increased flexibility. While Patent 1,967,208 to Krahl shows a spacer plate having a cathode aperture defined by two segments, the edges of the segments extend in angular dfrections thus reducing the flexibility of thesegments. Krahl shows only two segments for engaging his cathode sleeve while the spacer plate of the present invention has four segments for supporting a Therefore, a greater burden of support is assigned to each of the segments of Krahl thus making mandatory an increased rigidness of the segments. This degree of rigidness is not necessary in the case of the segments of the spacer plate of the invention, because the support of the cathode sleeve is distributed among four segments.

It will be apparent, therefore, that a novel jig and method are provided for facilitating the assembling of parts toform an electrode cage.

What is claimed is:

A jig for facilitating the mounting of an electrode on an insulating spacer plate, said jig having a planar surface for receiving said plate, a cavity in said surface adapted to be placed in registry with an aperture in said plate, and a plurality of fingers rising'from said surface and disposed around said cavity and adapted to be rece'ved in slots in said spacer plate, said fingers including a side portion adjacent said surface in registry with spaced edge portions of said cavity, and a bevelled side portion remote from said surface for forming a funnel for guiding an electrode into said aperture in the spacer plate.

, References Cited in the file of this patent UNITED STATES PATENTS

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