US937964A - Means for making castings by air-pressure. - Google Patents

Description

0. J. SAYERS.

MEANS FOR MAKING GASTINGS BY AIR PRESSURE.

APPLIUATIOH FILED JULY 16, 1907. q

' Patented Oct 2 SHEETS-SHEET 1.

Jill

INVENTOR.

WITNESSES,-

0. J. SAYERS. I MEANS FOR MAKING GASTINGS BY AIR PRESSURE. APPLICATION FILED JULY 16, 1907.

937,964. Patented 001;. 26; 1909.

2 SHEETS-SHEET 2.

UNlTEl) STATES PATENT OFFICE.

ORRIN J. SAYERS, OF CLEVELAND, O I -IIO, ASSIGN'OR TO RICHARD B. MOSER AND'FRED- ERICK J. LANGER, BOTH 0F CLEVELAND, OHIO.

MEANS FOR MAKING CASTINGS BY AIR-PRESSURE.

Specification of Letters Patent.

Patented Oct. 26, 1909.

Application filed July 16, 1907. Serial No. 384,016.

To all whom it may concern:

lie it known that 1. Oman J. Saunas, a citizen of the United States, residing at Cleveland. in the county. of ()uyahoga and State of Ohio, have invented a new and useful Means for Making Castings by Airlressure, of which the following is a specification.

.\l v invention relates to means for making castings by air pressure, and the invention comprises the means substantially as herein shown and described and more particularly pointed out in the claims.

As shown, my invention is especially adapted for making relatively small castings of gold, silver and like metals by air pressure and particularly for dental pur poses,such for instance as fillings for teeth, or for crowns, floors, backing's, plates or bridges for teeth. The invention is not necessarily limited to this class of work, but is preferably described therewith to more clearly define its chief object, and because such castings must be exceptionally perfect to be of practical use and value. Obviously, other ob ects enter into the make up of the device to simplify the. casting operation and to make a substantially self-operative machine easy to control and handle, and all as hereinafter more specifically set forth.

In the accompanying drawings, Figure 1 is a perspective view of my invention with a blow-pipe in operation, and showing both under hand control. Fig. 2 is a sectional view of a flask with a mold therein for easting a tooth filling such for example as shown in Fig. 3, said Fig. 3 being a erspective view of the casting as it comes rom the mold, gate and all, and showing its-relative place in a molar (dotted lines). Fig. 4 is a sectional view of a larger flask prepared for casting a backing to a porcelain facing, and Fig. 5 is'a perspective view of the tooth thus built up and ready to be attached to the root, except that the gate left by the casting operation has not been removed. Fig. (3 is a sectional view of a still larger flask having an investing or mold for a bridge casting. Fig. 7 is an edge elevation of a porcelain tooth having a floor and pin cast thereto, the root of the tooth being shown in dotted lines. Fig. 8 is a plan view of my device with its cover-open and showing a flask seated therein, and Fig. 9 is a side elevation thereof with the cover partly sectioned away to show the locking bolt which holds it open. Fig. 10 is a longitudinal section centrally of the device with the cover. closed and an valve open, but showing the air valve, intake nipple, and various other parts inplain elevation to more clearly bring out their inclividual conformation and also their-relation to the body of the device and cover. .In this view, a sectional view of a flask and mold is also shown as seated above the vent opening in the bottom of the device and with a casting therein as it appears when completed. Fig. 11 is a sectional viev. of the rear portion of the device showing a modified form of valve and means to automatically open andclose the same.

In detail, the invention consists of a flask confining receptacle -2 of any desired shape or f0rm,.but preferably constructed as shown with a flat'rectangular base 3- and walled body l of circular outline containing a relatively large chamber 5 open at itstop and having a smoothly finished flat bottom 6- upon which various sized ring-shaped flasks A may be removably seated A horizontally swinging cover or cap -7 is pivotally secured to the top and at one side of body 4 by screw 8 mounted within stud -9 centrally within circular recess 10- of the smaller circular portion -11- of the body. The contacting surfaces of the cover and the body are smoothly finished to make an air tight fit,- and moreover, said cover is provided with a in or handle 12 at its front edge which is adapted to enter open slot -1'5 in the upper end of stop plate l4 s..- oured to the front of body i and to engage its upper beveled edge -16 to press pin or handle 12 down and thereby force cover 7 to its seat, and serving also to hold the cover seated as against air pressure from below. The foregoing clamping means is simple and elfective for a small device such as shown, but in a larger device suitable adjustable means for taking up wear may be employed therewith, as is obvious.

Cover 7- is opened by means of handle 12 and when fully open as seen in Figs. -9-- and --10, a springpressed bolt 13 mounted on end within a vertical of the operator.

. from bolt ---13-- through side slot -19,- in

body portion l1---, and when thus released cover 7--- will close automatically under tension of coiled spring -2 0 located within recess 10 and which spring has right angled ends engaged with the cover and the body, respectively. The closure of the cover is practically instantaneous and should be quick and responsive and Without undue effort on the part of the operator because his attention and time is mainly occupied at this period in directing the flame from blow-pipe -B, see Fig. 1, upon the metal to be melted, and in watching the metal come to a. boiling or molten condition. As soon as this occurs prompt measures must be taken to force the metal while molten into the mold, and this result is brought .about by the release of the cover and-its automatic closure by spring 20. Thus, as cover '7- swings over chamber -5--, bolt opening 17- comes to rest directly over a second vertical bore '-2l in the rear end of body portion 11 and wherein a sliding valve 22 of bolt shape is seated. This valve has an elongated and reduced upper end 23- adapted to bear against the bottom face of cover 7- during its movement and whereby the valve is held in closed position and prevented from springing up under the pressure of coiled spring --2l' in the bottom of bore 21 until opening 17 is reached. Lifting of the valve by the spring opens air passage 27- leading from intake nipple -28 to chamber -5 and allows air under pressure to discharge into chamber -5 the moment cover 7 is closed and tightly locked. The sudden inrush of air into closed chamber 5- Will force the molten metal into the mold cavity, more or less, but in order that the same may occur completely and a perfect casting be obtained, I find that both the device and the mold must be constructed with particular reference to a vent or relief for the mold cavity.v To this end and for operative purposes, flask -A- is plac d within chamber 5 directly over vent passage -30 centrally located within bottom -6 and this passage may open into a supplementary air chamber in the device, or communicate with the outer atmosphere from and beneath base 3 as shown. Receiving chamber 5 is relatively large enough to hold different sized flasks for different (kinds of work, and for several reasons, I

predetermined size. In part, these reasons are convenience in handling the flasks, economy in the use of investing material,adaptability in drying or baking of the mold, and in removing the wax impression or pattern and also the casting from the mold. v

Now referring to the construction of the mold in particular. the best castings are obtained by using atleast two diiferent kinds (if investing material for "the mold; namely. a finely ground or comparatively dense material, and a coarse or comparatively porous material, the object being to provide a smooth outer coating -31-- for the mold top and mold cavity, and a more or less porous backing or open body -3Q* for coating -31--. A thin layer of relatively dense and fine investing material for coating ---31 contributes to the making of a smooth and deli-- air and gases in the mold cavity to escape during casting operations. and the coarser and more porous body 32 sustains the said finer wall or coating under pressure and obviously gives greater freedom for the escape of said air and gases to and through vent passage 30-.

However, I disclaim any novelty as to the use. of different mold materials for the purposes set forth, as the same is very common in foundry practice, nor doI lay claim to any special form of mold or flask or method of making the mold, because various forms and kinds ofmolds and flasks may be used with my invention. But for a better understanding of the operation of my device, I will briefly describe the making of a mold for single casts, and follow with the making of the casting. Thus, taking a Wax model of the object. to be cast, the same is supported in the center of the box or flask, such as a round flask A, by means of a needle or wire, one sufficiently large enough to form an ingate -.35-. The fine molding material is then adhered carefully toall parts of the model and its support, and when dry, a coarser mold-material is thrown in until the box is filled. The needle or ingate Wire is then withdrawn and the mold is burned and the wax model dissolved and removed. The mouth 34 of the ingate in the mold is also formed into a funnel or cup shape by the use of a founders spool, such as is ordinarily used for this purpose.

Now having the flask and mold finished,

moving locking. end 23 from opening 17- in the cover. This accomplished, the tiask is seated upon bottom -6- and over vent passage'30- and the operator places his gold or silver or other metal within the cup of the flask and directs a small pointed flame thereon, such as obtained by gas and oxygen from a hand controlled blow-pipe B, as shown. During this operation, the operator should be prepared with his lefthand to depress handle -l8 of releasing bolt l3.. Then, at the critical moment when the metal becomes molten and before burning thereof occurs, instant release of the cover is brought about bya slightdown pressure of his finger and the cover closes automatically and locks tightly and at the end of its movement permits valve -'22- to open-air passage 2T allowing air under pressure to fill chamber 5- and thereby force the molten metal into the mold cavity, the trapped air or gases i'n'said cavity being forced through the porous body of the mold and the vent or relief passage 30.

Either a rotary .or puppet-valve may be used in place of slide valve 22, and said valve or valves may be caused to close automatically by the opening movement of the cover. Such an arrangement is shown in Fig. 11, wherein rotary valve 38 limited to a quarter-turn or less, is adapted to be closed by a coiled spring -39- when disengagement occurs between projection 40 or its equivalent on the cover and pin t1- or its equivalent on the valve. The primary opening movement of the cover cuts ofl' the air before'ehamber -5 is opened, and again, when cover -7- closes, said closing movement at its end will open the valve against the tension of spring 39 and by the positive engagement be tween projection 40 and pin 41.

\Vhat I claim is 1. In means for making castings by air pressure, an open receptacle adapted to hold a flask and havin compressed air connections, and automatic means adapted to close said receptacle.

2. In means for making castings by air pressure, an air compressor device having a chamber adapted to confine a flask and selfclosing means for said chamber.

3. In means for making castings by air pressure, a flask receptacle having compressed air connections, and means to close the said receptacle constructed to control the air supply in combination with a flask adapted to be seated and air-confined within said receptacle.

4. In means for making castings by air pressure, a flask receptacle having compressed air connections, and automatic means to close the receptacle and confine the flask therein and also to control the air supply thereto.

5. In means for makin .castings by air pressure, a flask receptac e having a vent' opening for the flask and compressed air connections, and automatic means to close said receptacle t0 confine the flask.

(i. In means for makin castings by air pressure, a flask receptac e .having a vent. opening for the flask and compressed all" connections, andautomatic means to close said receptacle and also to control the air supply thereto.

7. .111 means for making castings by air pressure, a flask receptacle having compressed air connections and a movable member to close the same. and a valve for said air connections controlled by said member in combination with a flask adapted to be seated and air-confined within said receptacle.

8. In means for making castings by air pressure, a flask receptacle having an automatically operated member adapted to close the same,-and a valved air intake controlled by said member.

9. In means for making castings by air 11. In means for making castings by air pressure, a flask receptacle having a pivoted cover and a sprin to close the same andmeans. to hold sai cover open against the tension of said spring, and compressed air I connections for said receptacle.

12. In means for making cast1ngs-by a1r pressure, a flask receptacle having compressed air connections, a pivoted cover and,

a spring to close the same, a detaining lock for said cover, and an air intake valve engaged with said cover and adapted to open when the said cover is closed.

13. In means for making castings by air pressure, a flask receptacle havin a spring controlled cover and a detaining l ock therefor, an air intake for said receptacle and a valve operatively engaged with said cover, and a vent open to the flask when confined within said receptacle.

14. In'means for making castings by air pressure, an open receptacle adapted to hold various sized flasks and having a vent opening in its bottom, a self closing cover for said receptacle, and an automatically operative air intake valve adapted'to open when the cover is closed.

15. In means for making castings by air pressure, an open receptacle adapted to hold mold flasks, a self closing cover for said receptacle, clamping means to hold said cover tightly shut, and a valve air intake for said receptacle.

' lo. In means for making castings by air pressure. anropeu receptacle adapted to mold flasks-1a self-closing .coverior said receptacle and means to lock the same in closed position againstair pressure from Within, a

detaining member to hold said cover open, a

valved air intake for said receptacle, and a vent opening in the bottom of said receptacle adapted to he covered by the flask;

' ations. 4 i

18. In means forinaking castings by air pressure, a flask receptacle having an air chamber'adapted' touseat and confine a removable flask and having compressed air connections, and means towopen and close said air connections automatically.

19. In means for making castings by air pressure, a flask receptacle having an air hold chamber adapted to seat and confine a removable flask and having a cover and valved an connections, and automatic means adapted to close the said valved connections upon opening the cover.

20. in means .t'or making castings by air pressure, a flask receptacle having a cover and valved air connections, means to auto,- matically close said cover and open said valved air connections, and means to automatically close said valved'air connections upon opening the cover. v 2.1. In a. pressure casting apparatus, the combination with the receiver for the flask GDibOClYillg separable sections and a pressure supply duct and valve controlled by the closing of the sections to admit pressure to the receiver, of a catch for holding'the receiver; closed against the internal pressure tending to open the same.

In testimony whereof I sign this specification in the presence of two Witnesses this 9th day of July, 1907.

ORRIN J. SAYERS.

\Vitnesses F. J. LAUGER,

B. E. Mosnn.

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