US914783A - Sand-blast machine. - Google Patents

Description

F. P. BOLAND.

SAND BLAST MACHINE.

APPLICATION FILED NOV. 27, 1'908.

Patented 'Mar. 9, 1909.

//\/ VEN TCJR W/ TNEEEEE and communicating FRANCIS P. BOLAND, QF PROVIDENCE, RHODE ISLAND.

Specification of Letters Patent.

I SAND-BLAST MACHINE.

Patented'March 9, 1909.

Application filed November 27, 1908. Serial No. 464,729.

means and also in the construction of the mixing head or chamber, from which latter the abrading material is discharged via the outlet-nozzle, all as more fully hereinafter set forth and claimed.

In the. accompanying sheet of drawings, Figure 1 re resents a vertical sectional view, in partial e evation, of a sand-blast machine embodying my improvements. Fig. 2 is a vertical central section of the mixing head and its connections, in enlarged scale. Fig. 3 is a horizontal sectional view taken on line 3' 3 of Fig. 2. Fig. 4 is a vertical central sectional view, also in enlarged scale, showing the construction of the sand and air feeding device adapted to be located at the bottom of the sand reservoir, and Fig. 5 is a horizontal section, taken on line 5 5 of Fig. 4.

In my im roved sand-blast machine I employ a suita ly supported preferably square or rectangular casing 0 having glass sides, inclosing the working chamber a, a beveled top a and a sand reservoir e, the latter being located immediately below the chamber a therewith via the perforated plate '5. An extension f terminating in the exhaust flue 9 leads from the rear of the chamber a. The front side of the casing is provided witha swinging door 0 and a guard or protector w arranged with respect to the usual hand-holes d and located below said door. 'I make no claim to the ele-' merits before described.

An air-blast ipe h adapted to be connected with a suita le source ofair supply passes centrally downward through the top of the machine and terminates in the mixing head A," soon to be described. A branch .pipe m extends rearwardlyend downwardly fromthe pipe h and is secured-in the top' of thehollow casting B, in turn adapted to rest on and be supported by the bottom wall of said reservoir 'e. the respective pfiipes h and m are e'rnp contro ing the "Cocks k and m inter osed 4 oyedfor. ow of air. The sald'casting' ftion o the discharge-nozzle k relation to the plate B, shown more clearly in' Fig. 4, practically for IS a chambered return-bend, the air from the inlet-pipe m in this case flows clirectly therefrom through an open short upright nozzle 1) tapped into thetopof the cast-" ing. The lower end of what maybe termed the main circulat' -pipe a freely surrounds the nozzle 6 and is 25s ber B. One side of pipe u is provided with an opening t6 near the bottom extending to or nearly to the top of the nozzle, the upper portion of the latter being cut away at b on the side opposed to constructed the casting and the lower poro tapped into the memsaid opening u. As thus tion of pipes m and dare when in service completely surrounded by the sand or abrading material contained in the reservoir 6; the arrangement being such that the sand flows by gravity through opening a and fills the annular space 8 lying between the members a and I), while at the same time the ressure of the air issuing from the nozzle ii drives the sand from the space 8 and forces itupwardly in the circulating-pipe to be further mingled with air in the mixing-head A and finally discharged'from the latter onto the Work. The said member A comprises a casting provided with an enlarged cham bered cylindrical u per portion 0 having converging side wa s terminating at the bottom in a central nozzle 0 and having an upwardly inclined branch or nozzle n arranged tangentially to and being in continuous open communication with said chamber 0. The lower portion a of the member 'n, is secured tothe upper end of the circulating-pipe u. The inner Walls of the chamber 0 may be provided with suitably disposed integral lugs or buttonlike projections p;

these latter as well as the inwardly extending lug 0 located contiguous to one side of the outlet end of the tubular branch at are employed to break up the rotative or swirling action of the sand discharged into the chamber and cause it to fall in a more uniform or even manner so as to be acted'upon more efficiently by the air discharged from the mouth of pipe h at the annular point 0 Fig. 2. The thus acted upon sand passes, via tube 70, into 'said nozzle 0 and the telescoping tube is to the suitably shaped outlet nozzle k and is discharged therefrom onto the work supported beneath. A screw k may beem loyed for readily changing the posivertically I I am aware that it is a well-known practice to Provide sand-blast machines withmeans for continuously circulatin and re-using the sand. and therefore I disclaim such feature broadly, except as to the novel construction and arrangement of devices employed as set forth in the following claims.

I claim as my invention and desire to secure by United States Letters Patent 1.- Ina sand-blast machine, rovided with a'working chamber and a san reservoir lo-.

' cated therebelow, the combination therewith of a chambered member or casting B supported in the reservoir so as to be embedded in the .sand,'-a pipe for admitting air under pressure into the casting, a short outlet-nozzle secured to and extending upwardly from the latter, said inlet and outlet members being in continuous open communication with I the chamber of said casting, a circulatingipe also secured to the casting having its ower portion' perforated and inclosing said nozzle and forming. an annular space therebe-.

tween into which space'sand may flow by ravity but not' into the ca'stings chamber, a hollow head; member located in the said working chamber connected to and being in 1 continuousopen communication with the circulating-pipe foriintroducing l sand into the head, a nozzle connected wit the lower portion of said head, and means for forcing the thusintroduced sand downwardlyfrom the i head and discharging it through the nozzle,

substantially as herelnbefore described;

1 2. In a machine of the character described,

the combination of a chambered casting memberB constituting a return-bend, an et pipe m tapped into the'said member, a main circulatin -pipe it having its lower end tapped into t e member B but not extending .into its chamberhavin a lateral opening'through its wall, a sma ler pipe 6 forming anair-outlet nozzle tapped into the casting for discharging, air therefrom, and having said nozzle arranged concentrically with and inclosed by the circulatin -pipe so as to form a space between them, ti

upper edge of said lateral opening.

3. In a machine of the character described, the combination of a head member havin a 'mixin -chamber proper therein provi ed with ownwar'dly. converging side walls tere u per end of the nozzle extending to or beyon theminating at its lower end in a dischargeoutlet having a materially reduced cross sectional area, a pipe extending downwardly through the, head 1nto the chamber for admitting air under pressurefa branch nozzle opening into the mlgrlng-cliarnber, said nozzle being non-central or ofiset-with relation to the atter and also extending downward at an angle therefrom, and a circulating-pipe connectedto the lower or free end of said 4 branch nozzle for conducting sand and air from a source-of supplyinto the mixingchamber.

and a series'of short projections formed onthe inner'wall of the chamber'ior the purpose herein set-forth.

Signed t Prov'idence, R.. 1., this 24th day of November, 1908..

Witnesses:

OALvIN H. BROWN, GEO. H. REMINGTON.

FRANOISlfz'BOLAND.

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