US2602189A - Wax injecting machine - Google Patents

Description

July 8, 1952 A F|NELT WAX INJECTING MACHINE Filed NOV. 30, 1945 l2 SHEETS--SHEET l INVENTOR w um .A

July 8, 1952 A. FINELT WAX INJECTING MACHINE 2 Sl-IEETS-Sl-IEET 2 Filed Nov. 50, 1945 INVVENTOR wlw/fi I ATTORNEY a 7 7 f f f w w a 7%/ w ,b 3 M |e o m l 5 ...4 w u. N mgm Patented July 8, 1952 WAX INJECTING MACHINE e Aron Finelt, New Rochelle, N, YL Application November so, 1945, serial No. 632,001

L L scleims. 1

l This invention. relatesV generally `to i thel art of metal castingy and more; particularly to the production. of wax replicas 0f; articles to be cast.

As isr well known in the arttoz which the present-invention relatesl the. forming of parts. principally of castable metals, may' .be Vobtained byl making a,v negative mould of. the yoriginal object and then lling this` mould; repetitivelygwith: ,a seriesl o1" molten .wax 4injections to= produce wax replicas. These replicas turn are used toform negative. Ainipr'e'ssio'ns1'- iii casting fasks." "The .wax is melted-` and burned eu't of thef'castingfflasks vvhi'chw-lll:l then fill withinoltenlmetal'preferably on a centrifugal castingmachine; It is' amongl the objects of the'pi'esent invention v"to 'provide iently lling''the-mould;V Y

lies inthe lizi'rovi'sicn 'of a machine for rapidly; effectively, `and conven- Another" object herein reducing the"conta-'rhination of ythe-hielten Wax so that blemishes and porosity ofthe il-nisheclfA ca -sting are-reduced to a `Another objecthere'n lies 1n the provision of a wax injecting, machinefin whichjadequate-pres`- Another object herein liesfi'n the provision efcomplete juncture vat the nozzle,'the hotwaxj issplashed toward the machine .and away from the operator.

Another object herein liesjin the provision of means for Vreducingthe entrance o f waxinto the electrical heating :unit Withia consequent. improvement in theoperation of the latter..`

Another object hereinilies the provision of pressure operatdmeansor the inflection. of the hot wax andfwhich` automatically recharges iftself.

A feature. of ythe,prestiti nl hineliesthe factthatthepressureupon he Xbeingejected from thev machine.andv injecte into Aizl-iemould maybe manually .obtained orlroni an external pneumaticsource, Y Y Telf' i Aieature -ofthe` invention lies initheinterchangeability ot the nozzle. headteaccomnicdate dinerent kindsofmoul'ds-l Another feature vlies; in lthe ease ofJassembly and disassembly o-fejthe various parts. s o that the machine may be conveniently-cleaned, adjusted andserv'ced. j rl: s

These obiectsf andother incidental ends and advantages 'willmore fully; appear inthe progressof this disclosure and be minted outin theap handed: claims.; ;A e.; I

55 mometer support 28 In thefdrawngs in whiclrsimilar reference characters designate corresponding parts throughout the several views:

yFigure 1 isa side, elevationalviewpartlyrin central section or an embodiment. of, theinvention. y Figure 21s aA plan view with the cover in altered.position., 7 v .A ,l e, Figure 3 is a front elevationalview. ,I l"

l0 .Figure 4 is a viewofv anl'alternate forni of foot. i i, Y

The device generally lindicatedby reference. character l0 comprises broadly a basev l,l,- apot l2, heating means I3, a pot cover I4 and inject- 16 ingmeansi'r.y -Y f Thepot. l2 is preferably in. the form of anun-` wardly opening hollow vessel and asv shown may be circular in horizontal section. Disposed about the base of the pot l2 outwardly ofthe bottom Itis an annular trough. Leading fromthe trough l1 is an outlet I8 which may be connected t0 the conduit i9- byy theV coupling 20'., Theconduit; -I-S may travel to` any suitable container (not shown) for collecting the waxwhich has been gathered 25 by the trough l1. It is preferable that `the tubing; I9 be relatively short soA that it-may remain ata suiciently elevated temperature by virtueof` heat conducted to it from the pot and trough so that during normal operation the: wax will not con-z geal therein. v 1 `TheV base ll is preferably formed byf a down-` ward extension. of the vertical cylindrical wall` -of the pot andencloses the heater'` means which includes a 'heating element 21,; a. thennostat 22' 'andl a control box 23- Projecting'through the side portion 24`of` the Wallv 25 of the base I'l are aswitch 26 and a 'pilot 211. The thermostat` 'l2k is preferably set to open circuit at a temperature only slightly above the melting, point.l of the wax 40 30' and is hookedl in series with the 'switch'26- land-the heatingelement 2|. VElectrical energy-is conveyed' tothe-heating element 2r|vv by'wellknown conductors (not shown). lTheY pilloty k2T may be hooked across the power linesbetween theswi-tchand the, thermostat toshow when the'switchr isi in its on-position or it may be' hooked;Y across the power lines between the thermostat andthe heating element in which case it wil-1 indicateewhen current is flowing into theheating element. The thermostat 22 may be of the adjustable type/ and .may be regulated top roduce'the desiredamount ofheating yin the wax 3u as may` be determined- .,by an. inspection of the thermometer 2 9 which is detachably engageable by resting in the ther- The support 28de anv elon gated cup shaped body orifice 3| in the pot cover I4.

threadedly engaged in an The base I I is provided with a removable base plate 32 which is upwardlyv pressed against the gasket 33 by means of the screws 34 so that the electrical equipment enclosed within the base is substantially sealed) against contamination. The device in normal use over a period of time is subjectto frequent changes in temperature and owing to the low `viscosity of the wax at elevated temperatures the same has a tendency to seep through the gasket materials with a consequent contamination of the electrical parts. I have prevented this from occurring by the use of the trough I'I which collects any of thewax which may be running down the outside of the pot I2 and conveying it away where it cannot damage the heating element and associated v parts.

The base I is providedfwith a plurality of feet V35, each of which Vis penetrated by a screw 36 for securing the device upon any suitable working surface (not shown).` To facilitate attachmenty or removal of 'my device from the working surface upon which it is used, the feet 30 may be provided with keyhole slotsin a Well known manner. See Figure 4 in which' an alternate form of foot is shown. In thisl figure the foot |35 has a keyhole slot |37.

The cover I4 is preferable in the form of a flat plate having an annularrecess 40 containing a gasket 4|y whichwis adapted to coact with the rim 42 Aof the pot |23- Adequate compression upon the gasketl 4| is maintained by the thumb screws 43 which Vare threadedly engaged in orifices 44, in the arms 45 which are pivotally mounted by pins 46 in the'ears 41: When it Ais desired to remove the pot cover I4 the thumb screws are loosened and the arms swung downwardly and outwardly allowing convenient -access to the inside of the pot I2. The cover|4 is provided with a pneumatic or fluid pressure inlet 48, a pressure gauge 49, a pressurel control valve 50 anda pressure supply conduit A relief valve 52 is mounted upon the fcover I4V and acts to dissipate excess pressure occurring in the chamber area 53 above thewaX30. i f v The mould vfilling means 55, y as previouslyv stated, is adaptedV for manual or automatic pressure operation. When the means 55 is manually operated the main cylinder 56 is adaptedto reciprocate forwardly and rearwardly of the pot I2 and is slideably supported in an orifice 5'I in the forward portion 58 of the vertical wall of the pot. The orifice 51' centrally thereof has an annular channel within .which is disposed the gland packing 59.. Thepacking is maintained under compression by the gland nut 60 which engages the threads bordering the forward portion of the orifice 51. Outward movement ofthe cylinder 56, is regulated by the-adjustable collar 6|.' having a set screw 62 while rearward movement is' limited by the cap nut 6.3;` The limit 0f movement ofthe cap nut 'S-would occur no-rmally only when the capacity of the mould filling means 55 is insufficient to ll the mould. The piston element 65 is relatively stationary in normal operation and is supported at the forward portion thereof by a plurality of rings which engage the inner cylindrical surface of the cylinder 56, and said piston element is supported at the rear end 66 in a socket 6'I Vin the rear portion 66 of the -vertical wall of the pot I2." The piston element is in the form of an elongated tube 69, the rear end 66 of which is closed. The

. cylinder 56,v the various parts arev maintained protected with a screen or iilter i3.

4 rear portion of the tube 69 is provided with anv inlet port 'I0 which is tted with a ball check. valve II, and the entrance 'I2 to said valve is'- The ball check valve housing I4 and a stationary projection 'I5 act as a rear sup-port for the expansive helical spring -1 6. The forward end of the spring 'I6 bears against an oriced disc TI which rides upon Vthe tubetBS andbears Va'gaIist-the rear edge of the cylinder 56. E {Il'iefl rear end: of the cylinder 56 has an inside taper 18, fo-rwardlyconverging, which facilitates the insertion of the piston head 'I9 into the'cylinder 56. The piston headis preferably formed by mounting upon a portion of a reduced diameter a central ring 8|, and outwardly thereof a pair of cup shaped members'8'2. 'The ring 8| is preferably composed of rigid material while the cup shaped members are preferably composed of a kyielding material such as leather and said members are opfpositely disposed so that their cup openings extend'in opposite directions. Disposed within the cup openings of the members 82 are a pair of wash'- ers 83. The piston head I9 is-maintainedin. ,operative condition' bythe compression afforded by thenut 84 'engaged upon the threaded for- Ward end 'of the tube 69.` The nut 84 compresses 'theiwashers83 the members'02 andthe central ring 8| Yagainstfthe shoulder 85 in the tube 69.- g; z 'The feeding valve V8b has-Aa hollow valving member Vmounted forreciprocation'forwardly` and rearwardly Lof the jdevice I0. within the central :cylindrical opening 81 1 in Ythe cap nut 63. The feedinggvalve, 86 includes a nipple |00, a spring 88 and a spring support 89-as well as the member 90 and the cap nut 63. Thejvalving member 90 includes a plurality of angularly disposed passages 9| lwhich are opened bythe rearward movement of the member 90 which isaecompanied bya compression of the spring 8 6. The rear portion ofthe member 90 has a frustoconical flange 92 which is adapted-to seat within a correspondinglyv tapered flare in the rear-` mostportion loftheforice 8'I. The rearV end of the valving member 90 also has a central and rearwardly extending Vprojection which supports the spring 88 -byaxially engaging said spring. 'I'he forward end ofthe valving member 90 is provided with an external thread upon which the nipple |00 is threadedly engaged. This construction permits the substitution of various shaped nipples, having a standard vinternal thread, y for the nipple I00, to accommodate moulds having variously shaped wax receiving openings. `The Aspring supporti!!!VY is in the'form of a holl'owflanged cup having a perforated rear Wall as seen in Figure 1, lThe flange portion offthe support 'engages'. upon 'the forward end of the cylinder 56 and isV maintained in position by `the cap nut 63, l v VMarmaloperation may be substantially as follows. A fewreciprocations of the mould filling means 55 are preferably made to fill all ofthe desired channels with molten wax and by virtue of the thermal contact betweenthe frontpo'rtion 58'of the pot I2 and the gland nut 60 with at a suciently high ter'nperaturefy to prevent congealing of the Jiwaxftherein'. lFurthermore, the tube'69 and the valvel housing 'I4 areimmersed in the moltenwax so that adequate teniperaturey is maintained at these points also.

lWithA oscillation of thev cylinder 56 it 'too' is brought into contact with the molten Wax'and takes on heat therefrom. Assuming the means 55 to be filled with molten wax. the mould (not shown) is placed with its -opening against the nipple L08, and-fthe mould. isz moved-rearwardly toward the device l0. Since thespring 88.- is relatively stronger than the spring 1B, the valving memberl 9'!!y moves iso that the passages. 9i communicate .with the chamber 93 withinV the spring support 89: as. soon as the hydraulicback pressure is suicient. Further-rearward movement of the mould causes they cylinder 56.F to move rearwardly andl throughtheV disc H compresses the spring. .This re'duceslthe eiective internal capacity of the chambers; 94 and 95- producing positive pressurey in said chambers against'. the ball in the checlsvalvellwhich seats and the wax within..the chambers-99,. 94 and` 95Lis iniected into the mould throughs-the nipple |08. As soon as the mould is filled', since the wax is relatively incompressible, further movement of the mould and the parts just described of the means 55 is inhibited.

As soon as the wax strikes the mould, since the wax has been maintained within the pot I2 at a critical melting temperature, the wax congeals and as soon as the pressure of the mould is removed from the nipple the spring 88 closes the valving member 90 to prevent entrance of air thereat while the spring 1B then moves the cylinder 56 forwardly which produces reduced pressure in the chambers 93, 94 and 95. Gravity and atmospheric pressure force a new supply of wax from that contained in pot I2 into the chambers 93, 94 and 95.

Where the present device is operated from a source of external pressure the cap nut 63 may be moved into contact with the gland nutV 60 and the washer 6I may have its set screw 62 manipulated to keep the parts in this condition. The pressure is adjusted by means of the valve 58 and the gauge 49 to the desired value and when the mould is pressed against the nipple |80 the valving member 90 moves rearwardly to clear the passages 9 l and the wax flows through the ball valve 1l, the chamber 95, a relatively reduced size chamber 94, the chamber 93, passages 9|, and through the valving member 90 and the nipple |08. When the mould is removed from the nipple 108 the valving member 90 shifts forwardly under pressure of the spring 88.

It may thus be seen that I have disclosed a novel and useful wax injecting machine which permits complete filling of moulds and which may operate for long periods of time with a minimum of servicing attention, except the `rneplacement of the consumed wax.

I wish it to be understood that I do not ldesire to be limited to the exact details of construction shown and described for obvious modications will occur to a person skilled in the art.

I claim:

1. A device of the character described comprising: a receptacle having an opening in the front wall thereof, a threaded supporting nut removably secured therein adapted to support an injector unit, said unit comprising a cylindrical relatively movable barrel passing through said nut and supported thereby in horizontal position, a perforated disk secured to the inner end of said barrel, said disk having a central opening, a tubular relatively stationary plunger passing through the central opening in the disk and supported thereby, a piston packing disposed in said barrel and xed to the plunger near the outermost end thereof, a radially extending member secured to the plunger near its inner end, a helical expansion spring mounted around said plunger; the endgot'said'spring' bearing respectivelyl a'gair-istisaid radial member diskso: as tokeepl thei-innerend of the. plunger in. engagement 'with the rear' wall of' said'v receptacle, and normally to: keepi thebarrel.' in projectedi posia sleeve iinh threaded engagement with the outerK end ofr4 the "barrel, ay conical stem: valve slidabi-'y supported by the.y sleeve, a nozzle mounted on the outerE end of the" stem valve, aspri-ng withi'nthe sleeve: acting on the stemlvalveto hold it normally closed, saidf valvel st'ern'having a longitudinalduct and'` transverse ductsformed therein to aord a communicating passage`^ from the sleeve through the stem valve and nozzlewhen the stem valve ispushedinwardly, and a check valve located Orr-'said plunger neartheinner end thereof, wherebyvwhen the nozzle and bar-'reif are pushed inwardly fluid within the receptacle is ejected through the plunger barrel and nozzle.

2. A device of the character described comprising: a receptacle having an opening in the front wall thereof adapted to support an in- Jector unit, said unit comprising a cylindrical relatively movable barrel passing through said opening and in horizontal position, a perforated disk secured to the inner end of said barrel, said disk having a central opening, a tubular relatively stationary plunger passing through the centralopening in the disk and supported thereby, a piston packing disposed in said barrel and fixed to the plunger near the outermost end thereof, a radially extending member secured to the plunger near its inner end, a helical expansion spring mounted around said plunger, the ends of said spring bearing respectively against said radial member and disk so as to keep the inner end of the plunger in engagement with the rear Wall of said receptacle, and normally to keep the barrel in projected, position, a sleeve in threaded engagement with the outer end of the barrel, a conical stem valve slidably supported by the sleeve, a nozzle mounted on the outer end of the stem valve, a spring within the sleeve acting on the stem valve to hold it normally closed, said `valve stem having a longitudinal duct and transverse ducts formed therein to afford a communicating passage from the sleeve through the stem valve and nozzle when the stem valve is pushed inwardly, whereby when the nozzle and barrel are pushed inwardly uid within the receptacle is ejected through the plunger barrel and nozzle.

3. A wax injecting machine for use with a mold comprising: a first chamber adapted to contain wax, said chamber including a vertical wall having an opening; pump means slidably disposed within said opening and forming a substantially fluid tight seal, and including a second chamber the effective size of which may be varied; first resilient means urging said chamber in the direction of its maximum capacity; uni-directional meansto admit uid from the first chamber to the second chamber; and an exit means on said second chamber, said exit means being disposed outwardly of the first chamber; and means to lock said pump means in such position that the elective size of said second chamber is at its minimum capacity.

4. A device of the character described comprising: a receptacle having an opening in the front wall thereof adapted to support an injector unit, said unit comprising a cylindrical relatively `movable barrell passing through said opening and in horizontal position, a tubular relatively .stationary plunger extending into said barrel,

means on said plunger forming, a packing between said plunger and the inner ysurface of said relatively movable barrel, an enlargement on said plunger, mounting means having a resilient component disposed between 'the enlargement on the plunger and the inner end ofV said barrel, whereby the inner end ofthe plunger is engagedwith the rear Wall of said receptacle, and normally to keep the barrel in a projected position, a downwardly projecting inlet Valve onfsaid plunger, and an outlet valve on the outer end of said movable barrel, whereby fluid wax may travel in `an upward direction through saidinlet valve into said plunger. l

5. Structure as claimed in claim 4in which the inlet valve is gravity actuated to the closed position thereof. l

ARON FINELT.

8 REFERENCES CITED The following, `references arey `of'freeord in the file of thispatent:

u UNITED STATES PATENTS Number j NameA Date f 633,872 Mackin Sept. 26, 1899 784,788 Gustafson Mar. 14, 1905 1,385,781 Eynon July 26, 1921 1,703,286 Zerk l Feb. 26, 1929 1,796,645 Carrington Mar. 17, 1931 2,120,333 Kubo June 14,v 1938 2,207,426 Bailey vJuly 9, 1940 2,243,293 t Stahl l May 27,1941 2,359,840 'Goessling Oct. 10, 1944 2,422,990

,Spanier June A24, 1947

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