US1020709A - Aspirator. - Google Patents

Description

C. W. NANCE.

ASPIRATOR.

APPLICATION FILED APR. 1, 1910. RENEWED rm. 6, 1912.

I in: E E

I Patented Mar. 19, 1912.

UNITED STATES PATENT OFFICE.

CHARLES WESLEY NANCE, OF LONDON, ENGLAND.

ASPIRATOR.

Application filed April 1, 1910, Serial No. 552,870.

To all whom it may concern:

Be it known that I, CHARLES WVnsLnr NANCE, subject of the King of Great Britain, residing at London, in the Kingdom of England, have invented certain new and useful Improvements in Aspirators, of which the following is a specification.

This invention relates to an aspirator appliance operated by an impellent liquid for the purpose of exhausting the air, vapor and gases from hermetically sealed chambers or vessels and their contents, and is particularly serviceable because of the rapidity of its action where suchchambers are of large dimensions and also where such are used for the evaporation of liquids.

The invention is best described by aid of the accompanying drawings, in which,

Figure 1 is a sectional elevation; and Fig. 2, a section on a somewhat larger scale of a certain detail.

In these, A is a tank having a refrigerating device B therein, which can be simply an ice chamber having a passage or passages C through it. D is an exit from this cham ber leading to a pump not shown, from which the water is driven into the passage D D ends in a contracted orifice D in a chamber E having an air compression chamber E above, with preferably a gage E to show the pressure.

F is a contracted portion of chamber E ending in a small'straight passage, and on the lower end of this passage is a friction rose having a series of small perforations usually a quarter of an inch in diameter through it. Where however a nearly perfect vacuum regardless of expense is required, I form a single cylindrical perforation about 5*; the diameter of the pipe, and in proportion as the vacuum can be less perfect and it is desirable to have greater quantity of work performed, so are the perforations made smaller and more numerous. This rose G is held in place by a screwed collar G H is the pipe leading from the chamber to be exhausted, and H a non-return valve therein. This pipe leads down to a tapering or conoidal tubular receiver just below the rose G ending in a passage H which is the narrowest part of the receiver and about the diameter of the bunch of jets. The gases drawn into this narrow part H cannot escape back. This passage H has an enlargement H lower down. This is useful but Specification of Letters Patent.

Patented Mar. 19, 1912.

Renewed February 6, 1912. Serial No. 675,911.

not absolutely necessary, but is advantageous as lessening the change of back action. A little annular pocket H also assists in this way. The enlargement I-I opens out into a chamber I, from which a passage J delivers the impelling liquid back again into the chamber A ready to pass through the refrigerating device B C and renew its operation. It is desirable that the distance between the part Q containing the passage H and the rose G should be capable of adjustment. I therefore arrange the device shown below it in Fig. 1, and in Fig. 2. In these K is a hand wheel at the end of screwed shaft K screwing through a stuffing box L with check-nut L, Fig. 1, and having arms N fitting into holes in a screw nut N having the same pitch of screw as K has.

P is a shaft having a small wheel at the end screwed through K, and having a piece P having projections I fitting into depressions in the end of the casting Q. Q, is screwed into the walls of chamber S. When therefore it is desired to adjust the distance between the rose G and the passage H the hand wheel K is first turned, unscrewing the check-nut N the hand wheel on P is then turned, screwing backward or forward the piece Q. WVhen this movement has been finished with shaft P the check-nut N is driven into place.

The mode of action of the device is as follows :The pipe H being connected with the chamber to be exhausted, a pump not shown in the drawing, connecting D with D is put in motion, forcing the refrigerated liquid from the chamber A through the part D and D. This projects a stream of water with great forcethrough the openings in the rose G forcing the air or vapor through H and H with it into the chamber I and thence down J back again into the tank where the vapors are liberated while the liquid goes on and passes through the refrigerator to the pipe D. The object of the rose G is in order to cause a very large amount of friction between the surface of the water and the vapor coming down pipe H as the entire area being divided into a large number of small jets the whole circumference of this jet has a friction on the air or vapor. Where it is not desired to have an absolutely perfect vacuum it is desirable to have a very considerable length between F and Q much more than that shown in the drawing, while if it is desired to have an extremely high vacuum then a very narrow opening between G and Q is all that is desired. The object of having the refrigerating device is this. It is a wellknown fact that it is not possible by means of a current of water to produce a vacuum which is higher than the vapor tension of the water at the temperature at which water is employed. In order therefore to produce a higher vacuum thanis possible with water at the ordinary temperature I cool the water in the circulating tank by means of the refrigerator. Any other refrigerating means can .be used for this purpose. By working with water at or near the temperature of melting ice the vapor tension of the water is about 4.6 mm., whereas the vapor tension of water at 60 degrees Fahr. is about 13 mm. In order to still further improve the vacuum Which may be obtained by this arrangement of plant I make use of the natural law that the vapor tension of water is reduced when it contains salts in solution, and I prefer to use for my liquid a solution of a very soluble salt, since the reduction in Vapor tension is largely dependent on the amount of salt dissolved in the water. Owing to the cheapness of the material I prefer therefore to use calcium chlorid.

When the pump is used for producing a vacuum in a vessel containing a watery solution, the water in the vessel is evaporated and condensed in the liquid employed in the pump, and means have therefore to be provided for keeping up the concentration of the liquid or for evaporating down the liquid occasionally in order to bring it back to the required condensation.

I declare that what I claim is 1. In aspirators, the combination of a refrigerated water chamber, a chamber open to the gases to be aspirated, a passage connecting said chambers, a parallel perforated nozzle terminating the passage into the second chamber, and much smaller in diameter than the average Width of the passage between the two chambers, and adapted to divide the exhausting liquid into a series of parallel solid jets of liquid separated by vacant spaces, and projected out into a Wide chamber open to the gases to be aspirated, and a conical receiver on a line with the axis of the nozzle of much greater width atits wide end than the nozzle, but narrowing to about the diameter of the nozzle at a distance of about three or more diameters therefrom, and means for adjusting the relative position of the rose and receiver on the same axis on the outside of the aspirator while it is at work.

2. In an aspirator, in combination, a casing in close proximity to the lower end of the exhausting tube, a perforated rose mounted in said casing and adapted to receive or discharge a liquid under pressure rose provided with parallel perforations at the end of the exhausting tube, dividing the exhausting liquid into a series of parallel jets, a receiver adjustably mounted on said casing below said rose, and an internally and externally screw threaded check-nut engaging screw threads on the lower part of said adjustable receiver, and the inside of said casing respectively.

4C. In combination, in aspirators, a perforated rose located at the lower end of the exhausting tube, and adapted to divide the exhausting liquid into a series of parallel streams, a receiver adjustably mounted in said casing below said rose, said receiver having a downward tapering passage and nicks in its lower end, a hand wheel and shaft, and projections mounted on the end of said shaft for engaging said nicks.

5. In combination, an aspirator, a casing, a perforated rose located at the lower end ,of the exhaust tube in that casing, and

adapted to divide the exhausting liquid into a series of parallel jets, a receiver adjustably mounted on said casing below said rose, a check-nut screwed around the lower end of said receiver, and into said casing, and means for unscrewing said nut from the outside of said casing.

6. In combination, in aspirators, a casing, a perforated rose located in said casing at the lower end of the exhausting tube and adapted to divide the exhausting liquid into a series of parallel jets, a receiver adjustably mounted in said casing below said rose, a check-nut screwing into said casing against the lower shoulder of said receiver, and means for unscrewing said nut from the outside of said casing.

7 In combination, in aspirators, a casing, a perforated rose located in said casing at the lower end of the exhausting tube and adapted to divide the exhausting liquid into a series of parallel jets, a receiver adjustably mounted in said casing below said rose, a check-nut screwing into said casing against the lower shoulder of said part, and means for unscrewing said nut from the outside of said casing, the hand wheel and shaft and projections secured to the upper end of said shaft adapted to engage recesses in the lower edge of said receiver for varying the position of the same.

8. In combination, in aspirators, a casing, a perforated rose located in said casing in close proximity to the lower end of the exhausting tube and adapted to divide the exhausting liquid into a series of parallel jets, a receiver adjustably mounted in said casing below said rose, a check-nut mounted in said casing against the lower shoulder on said receiver, a hand wheel and shaft projections secured to the upper end of said shaft and adapted to engage recesses in the lower face of said nut, and means for varying the position of said art in relation to said rose from the outside of said casing.

9. In aspirators, the combination of means for refrigerating water, means for bringing this water to a rose perforated with a series of parallel perforations dividing the water into parallel jets, means for bringing the gases or vapor to be aspirated into a chamber in front of this rose, a conical receiver in front of the rose, and in its axial line at a distance from the rose equal to two or three diameters of the rose, whereby the group of jets pass for a considerable distance through the vapors to be aspirated, entangle the latter in the void spaces between them, and carry the vapors with them through the narrow part of the conical receiver, there being no impediment in the space surrounding the jet preventing the free access of the gases or vapors to the jets for a length equal to several diameters of the rose from the latter and the vena contracta or narrowest point of the receiver being about the diameter of the bunch of jets, whereby the gases once drawn into the gradually diminishing funnel cannot escape back.

In witness whereof, I have hereunto signed my name this 3rd day of March 1910, in the presence of two subscribing witnesses.

CHARLES WESLEY NANCE.

Witnesses:

RIPLEY WILSON, R. O. WILLIAMS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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