US2673784A - Exhaust machine - Google Patents

Description

March 30, 1954 w. s. SNYDER EXHAUST MACHINE 3 Sheets-Sheet 1 Filed Jan. 23, 1947 INVENTOR- l i lliamifinyder fiMw/ k Hls Attorney March 30, 1954 w. s. SNYDER EXHAUST MACHINE 3 Sheets-Sheet 2 Filed Jan. 23. 1947 R m W W.

mllidrn zsdsngdel' BY Y I 111's flttarmgy March 30, 1954 w. s. SNYDER 2,673,784

EXHAUST MACHINE Filed Jan. 23. 1947 a Sheets-Sheet :s

IN V EN TOR. hi ll iam S. Snyder fi/W WM His Attorney Patented Mar. 30, 1954 PATENT OFFICE;

2,673,784 EXHAUST William S. Snyder, Emporium, Pa., assignor to Sylvania Electric Products, :Inc; a; corporation Me sen er? ApplicationJanuaryfl, 194 7 ,rs rialNo, 723.786

This invention relates toexhaust achines for eleotron discharge devices and the, likef'and' to the electron bombardment and the getterin of v such devices, customarily effected during" their evacuation and prior to their tipping-off. The

invention relates to the machine, and (is, not necessarily. restricted to. electron discharge ode-Y vices as such, but; extends also to other devices 2 which may be ,enclosedin evacuated vessels, such as v relays and thermaLswitches, which may be in e vacuum orffin a. vessel initially, evacuated and, later charged with a special gas.

Vacuum tubes, ga eous tubes,v and other devices, which have metal parts enclosed in a vessel or envelope that is evacuated. at some part of the manufacturing process commonly have a gettering tab arranged.criticallyin relation to e q ma n er 'r h ecta art hose metal arts ca'n. be. inductively" heated by, radio frequency,.current lto have lion .7 the I gases fincluded within oron thensurface gthemetahand, after final evacuatio n' of gases, thergjettering tab may independently be, inductively, heated for flashing, Asis well known the. flashing vaporiz'es the gettering vmetal whichfledsorbsg ininute quantities;-t,;ga s remaining. object ,of the ,presr-f ent 7 invention is to. rovide; new, and, effective. omba nt fi ,P '-fl j i e; vic s qli xr r heist mach e In, one line of tiny radio, tubes, including i controlled; as typesftheg ette ns eb is l o' l dr i b t h J c-J tionof ,the Y vexhaust tribulation. with the remain-V fi um. type nd gri den of the envelope, and atan. an l tothe' come mon axis o f the exhaust tubulation and the en-d velope. It is a further-vobjectfof.thisrinvention otnrovid tro m ard e t p s irk a mg the, metal-- parts; er? 'siichif'dey'i esfwithoutr fiashi g; the getter, and ,for'indpendently.flash-r ing the getter without undulyheatingthemetal parts. A, further object is, to improve, the. construction of induction-heating coils for getter-t flashing and ,like purposes.

The embodiment of L the invention for accon plishing'theseobjects includesa carrier for movingthe unevacuated vessels or. envelopes, c on-, tainingthe metal parts andthe gett erin'g tab, successively past the bombardmentcoil and the getter flashingcoil which areusualintexhaust machines. In the present machine thebombardk mentcoils, are located-adjacent the pathof the vessQl; While thegettergflashing coil is. recipe oceble; n o an out l f he at f h v ssel it is carried through the exhaust cycle," The} et erlash n ilshqu dl deve op afield iii-" metals-i ter! 6 Cl ims-o mean) 2 tense enough to flash. the getter, while at the sanieijtime it should be directed so that nofin ten e partof it willundulylreh'eat the previously bombardeclmetal' parts enclosedin the vessel? Tothi'sf end the getter-flashing coilisso shaped f asfto' partly embrace the vessel and allow rel ative reciprocation parallel'to the envelope which'f is in getter-flashing position, portiqfisof each- "Fig. 1 is a fragmentary plan viewer an exhaust machine embodying thelpresent invention; showing one of a series 01 bombardmentstaf tions and the getter-flashing station;

Fig. zflis an elvationrpartly sectio bombardment station getter flashing station;

Fig 4vis anen1arged view, partly in section, of the gette'nflashihg coil in relation to the 'et- -Fig. 3 is an elevation, partly in section, of the ter, the enclosing vessel being "partly broken" away to show the getterjing tab;

Fig, 5 is an ehIarged'partIy sectional view of thelbombardment coil in itsfrelationjship to an" electron discharge devicelfthe internal elements'j of which are disclosed by a broken-awayi section;

of its'fenvelopeg Fla, 6 is an end view of the coils in Fig. 5; and

Figs. 7 andfl are aplan' viewfand a lateral ele f vation'respectively, of 'the getter fiashing coil'fin" EfigsQl,'3 ,and'4.

Referring now to the drawings, there will be describeda preferred arrangeinent for pemba q:

mggthe 'metal, electrodes (Fig; supported within, g'lassflve ssel v onjleadsL'which are sealed throughthe glass. An exhaust tubulation If is attached to vessel V, by means of which the vessel is supported while being exhausted,

- bombarded, while, the getter is being flashed, and

until. the time that, the junctiorr of tribulation Tfand vessel V is heatsoftenedftoseal on the vessel. Exhaust tubulationT also serves as the connectionbetween vessel V and the exhaust system in thejmachine for evacuating the vessel before, and during the bombardment, and to simply. anyfnecessa'ry gas to; the vessel. As shown in Figs. 4 and 5,'a getter element G is supported on the ssernblyjo i electrodesE and is ,cti n bi; Y SQIV h 3211- 3 lation T and at an angle to the common axis of the vessel and the tubulation.

Each tubulation T is supported vertically on a bracket I2 carried by turret l0, being gripped within the end M of a line (not shown) through bracket I2 to an exhaust pump. The turret is intermittently indexed to carry the vessels being evacuated in a horizontal circular path successively past a series of exhaust stations, the last of which is shown at A in Fig. l, and then past getter-flashing station B and ultimately to a tipping-off station where the junction of vessel V with exhaust tubulation T is fused and the vessel is removed from the machine. In the present instance the long dimension of the electrodes is along the axis of the vessel.

A two-part bombarder coil l6 of metal tubing is supported adjustably at station A with its axis at right angles to the path of vessels V and to their axes. With the coil axis arranged thus radially of the turret, it is possible to develop a uniform high-frequency field for heating electrodes T and thus driving off the occluded and the surface gases. This induction heater is best shown in Fig. wherein the two parts of the coil are shown joined by metal coupling 18. Multiple cords 20 of glass fiber hold the several turns of each layer of turns close to each other but insulated apart, and a flexible sheet 22 of insulation separates the layer of the coil. A high frequency generator (not shown) energizes the coils which are conventionally cooled by circulating liquid within the tubing. Coil i6 is carried adjustably by insulating block 24 clamped to rod 26 upstanding from segmental rim 28, carried in turn on rod 39 projecting from stationary bracket 32 on the machine base. The axis of coil Iii is at a level midway along the length of electrode assembly E, and is radial of carrier Ill.

At station B the getter-flashing coil 34 is shown. This coil is similarly of metal tubing for circulation of cooling fluid and is also energized from a high frequency source (not shown). When coil 34 is in position for flashing the get ter (Fig. 4) itis in the path of vessel V, but the turret is stationary at this time. Coil 34 is sup ported on insulating block 36 carried by rod 38 on segmental support 40. Unlike support 28,

segmental support 40 is vertically movable, bet ing carried by slide 42 in stationary guide 44 on the mach ne base. At the lower end of slide 42. cam follower 46 is in engagement with cam 48 on shaft 59 which rotates once for each operation of the turret indexing mechanism (not shown), so as to lower the coil after carrier [0 comes to rest and raise it before renewed in-'- dexing has commenced.

From Figs. 4, '7 and 8 it will be evident that coil 34 is free to reciprocate vertically while embracing vessel V, and that the upper half of each turn of the coil lies in a plane parallel to generally flat getter element G. The lower portions of the respective turns are bent out of the plane of the aforementioned parts of the several turns, in order that the coil may be raised freely. Were the entire coil merely made of oblique helical turns the field would be either too weak to flash the getter, or if strong enough, would harmfully reheat the electrodes E. The bent-away portions of each of the turns produces a field more or less transverse to exhaust it isneither wasteful nor damaging.

Just as in the case of bombardment coil I6,

, said envelopes.

coil 34 is made in two layers separated by a. sheet of insulation 22, and the several turns of the coil are held together but separated by cords 28 of glass fiber.

The sequence of operations in this machine follows that in other well known exhaust machines, in that a series of bombardment stations is followed by a getter-flashing station. The orientation of the bombardment coils and the getter-flashing coil is such that the action of each is relatively independent of the other. However, the particular configuration of the getter-flashing coil which promotes emcient flashing, in relation to the small vessel described, requires a special positioning of the bombardment coils if reheating of the electrodes is to be avoided. It will be recognized that the various parts are subject to modifications by those skilled in the art, and that the novel construction may be used for other purposes. Therefore itshould be understood that the specific disclosure is intended to be illustrative and not as a limitation.

and getter-flashing positions, an induction heating coil located laterally of the path of the envelopes for inductively heating the contents thereof, a getter-flashing coil mounted for movement into the path of the envelopes, said last mentioned coil being so warped so as to closely embrace a portion of each of the envelopes in succession, and means for alternately moving the coil into said path and removing it in timed relation with the movement of said carrier.

2. The combination according to claim 1 where'n said getter-flashing coil includes a plurality of turns most of each of which lies in respective parallel planes intersecting that envelope which is in getter -fiashing position, the remainder of each of the turns being bent away from said planes and from the envelope.

3. The combination, in an exhaust machine 3 for electron tubes having an enclosing envelope obliquely, a stationary induction heating coil adjacent the path of the envelope having an axis transverse to the path and axis of the envelope,

and a getter-flashing coil reciprocable into and F out of the path of the envelope having turns only part of each of which lies in a plane parallel to the gettering element when the envelope is in getter-flashing position whereby substantially only said getter element is heated by said getter flashing coil.

4. In an envelope exhausting machine, a car rier for moving said envelope successively past an induction heating station and a getter flashing station, induction coils at each of said stations, the coil at the first mentioned station being located laterally of the path of said envelopes for heating conductive material within said envelopes, the coil at the second of said stations being laterally movable into and out of the path of said envelopes in timed relation with the movement of said carrier, and said last mentioned coil being so curved as to partly embrace a portion of each envelope '5, In an envelope exhausting machine, a carwhen in the path oirier for moving said envelope successively past an induction heating station and a getter flashing station, induction coils at each of said stations, the coil at the first mentioned station being located laterally of the path of said envelopes for heating conductive material within said envelopes, the coil at the second of said stations being laterally movable into and out of the path of said envelopes in timed relation with the movement of said carrier, and said last mentioned coil including a plurality of turns most of each of which lies in a plane parallel to an element within said envelope, the remainder of each of said turns being bent to lie in planes at an angle to said element whereby only said element is heated to a substantial extent, and being so curved as to partly embrace a portion of each envelope when in the path of said envelopes.

6. In an envelope exhaust machine, a carrier for moving said envelope successively past an induction heating station and a getter flashing station, induction coils at each of said stations, the coil at the first mentioned station being 10-- cated laterally of the path of said envelopes for heating conductive material within said envelope. the coil at the second or said stations being laterally movable into and out of the path ofsaid envelopes in timed relation with the movement of said carrier, and said last mentioned coil having a number 01' turns, an arc of each of which lies in a surface partly embracing said envelope when in the path of said envelopes, the remainder of each of said turns being bent to lie in a surface at an angle to the surface of said are and away from the envelope.

7 WILLIAM S. SNYDER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,758,004 Madden May 13, 1930 1,904,214 Fagan Apr. 18, 1933 2,006,771 Kayko July 2, 1935 2,452,162 Stanton et a1. Oct. 26, 1948

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