US2489097A

US2489097A - Method for projecting streams

Info

Publication number: US2489097A
Application number: US725250A
Authority: US
Inventors: Roy L Luce
Original assignee: Hydro Blast Corp
Current assignee: Hydro Blast Corp
Priority date: 1947-01-30
Filing date: 1947-01-30
Publication date: 1949-11-22
Anticipated expiration: 1966-11-22

Description

1949 R. L. LUCE 2,489,097

METHOD FOR PROJECTING STREAMS Filed Jan. 30, 1947 AJI'I/ f9 JzZ/yeazz J? m,

Patented Nov. 22 1949 FQR PRQJECTING STREAMS Roy L. Luce, Chicago, Ill

Blast Corporation, of Illinois assignor to Hydro- Chicago, lit, a corporation Application January 30, 194 7, Serial No. 725,250

(Cl. l--282) 3 Claims.

This invention relates to method for projecting liquid streams and more particularly to the projection of liquid, which may or may not contain abrasive material in suspension, in the form of an unbroken high velocity jet.

In many operations, as in liquid sandblasting hydraulic mining, and the like, it is desirab project streams of liquid through substanti l o tances without having the jets break-up droplets or spray. With a plain nozzle, it 1' been found that the liquid jet tends to breakup or fuzz into a series of disconnected droplets or into a relatively fine spray within a short dis tance of the nozzle. A broken jet of this type i far less effective in liquid blasting or other hydraulic cutting operations than an unbroken stream.

It is one of the objects of the present invention to provide a method of projecting liquid strean in which air is added to the stream to be entrained thereby shortly before the final discharge of the stream.

Another object is to provide a method of pro jecting liquid streams in which the stream passed through an auxiliary nozzle prior to its final discharge and has air added thereto immediately prior to its entrance into the auxiliary nozzle.

Still another object is to provide a method of projecting abrasive material with liquid in which abrasive material is first added to the liquid air is subsequently entrained by the liquid prior to its discharge.

The above and other objects and advantages of the invention will be more readily apparent from the following description when read in connection with the accompanying drawing, in whicl Figure l is a partial side elevation of a liq sandblasting apparatus for carrying out method of the invention;

Figure 2 is an enlarged partial section of the discharge end of the apparatus, and

Figure 3 is a transverse section on the line 3-3 of Fig. 2.

Fig. 1 illustrates a liquid sandblast gun or the type more particularly described and claimed in the patent to Tirrell No. 2,200,587. As shown, the apparatus comprises a liquid blast gun formed by an elongated housing or casing it having a ban i grip H at its forward end and an arm rest ii. at its rearward end. Liquid such as water under high pressure is supplied to the gun through a hose I3 and flow of liquid may be controlled by a valve having a handle It. When the valve is open, liquid will flow at high velocity through the gun and through one or more internal nozzles carried by the housing it. As seen in Fig. 2, two such nozzles are employed, one of which, indicated at E5, discharges a high velocity jet of water through a relatively enlarged space into the second nozzle to which is aligned with and of slightly larger diameter than the nozzle l5. Abrasive material may be added to the liquid jet between the two nozzles through a supply connection I! which may be connected to a source of abrasive such as a flowable mixture of sand and water, as described more fully in the Tirrell patent. Passage. of the water jet through the space between the nozzle-s will create vacuum to draw the abrasive material into the jet to mix therewith. If desired, air may be added to the liquid stream prior to entrainment of the abrasive material through a valve nipple it, :as described in the Tirrell patent. It will be understood that any other desired type of liquid discharge apparatus such, for example, as that particularly described and claimed in the patent to Smith No. 2,040,715 could be employed equally well according to the invention and that addition of the abrasive material to the liquid stream could be omitted if desired.

According to the present invention, I have found that the stream or jet of liquid either with or without abrasive material suspended therein which is discharged by the nozzle it tends to break-up within a relatively short distance of the nozzle so that it cannot be used eifectively for cleaning or cutting purposes except at relatively short ranges. According to the present invention, this breaking up of the stream or jet is minimized and delayed by the addition of air to the jet shortly before its final discharge. I have found that the addition of air at this point is highly effective even though air has previously been added to the jet through the valved nipple It, as described in the Tirrell patent.

As shown, an auxiliary nozzle indicated generally at It is attached to the discharge end of the nozzle to in alignment therewith and provides for the addition of air to the stream or jet between the two nozzles. As best seen in Fig. 2, the nozzle 5 is formed by an outer sleeve 2! which may be threaded onto the end of the nozzle structure it and which carries an internal nozzle The nozzle is aligned with the nozzle l6 and has a slightly larger bore than the nozzle [6 to receive the jet of liquid therefrom. A spacer ring 23 is mounted between the ends of the nozzles 22 and it to hold them properly spaced apart and is of larger diameter than the bores in the nozzles. To provide for the addition of air to the stream, the ring 23 is formed with a series of air inlet openings 24 and is under-cut on its exterior surface to provide an annular space communicating with atmosphere through openings 25 in the sleeve 2|, With this construction, the nozzle 22, which may be subjected to a certain amount of wear, may easily be removed and replaced as required.

In operation, as the liquid jet passes from the nozzle I6 through the sleeve 23 into the nozzle 22, it will create a partial vacuum in the sleeve 23 to draw air in through the openings 24 and 25. This air will be entrained by the liquid jet and will be mixed therewith in the travel of the jet through the nozzle 22 so that the stream as finally discharged comprises a mixture of liquid and air with the possible addition of abrasive material. While the exact reasons are not entirely clear, it has been found by actual experiment that this stream will stay together in the form of an unbroken jet and will not fuzz or produce spray for a much longer distance then jet produced without employing the present invention. The efiects are equally noticeable even though air has previously been added to the liquid through the valved nipple 18 so that an effective jet can be thrown for a much longer distance with the present invention than with ones of the type shown in the Smith and Tirrell patents or with a plain liquid nozzle.

It has further been found that the addition of an excessive quantity of air between the nozzles l6 and 22 will cause the stream to break-up into a spray very rapidly. This action occurs, for example, when air is supplied through the openings 24 under a super atmospheric pressure. Experiments have indicated that supply of the air under atmospheric pressure in substantially unrestricted quantities produces optimum ressults. The size and number of the air inlet openings 24 and 25 may be controlled by design to insure the introduction of the proper quantity of air into the liquid stream. It is also important that the nozzle 22 be slightly larger than the nozzle It to accommodate the increased volume due to the addition of air, but that it be not too large or air will tend to flow into the nozzle counter to the liquid stream to assist in satisfying the partial vacuum produced in the sleeve 23. The nozzle 24 should, therefore, be of a size such that it will maintain the jet confined without tending to compress it.

While one apparatus to carry out the method of the invention has been illustrated and described, it will be understood that this is not intended as a definition of the scope of the invention, reference being had for this purpose to the appended claims.

What is claimed is:

1. The method of projecting abrasive material with liquid which comprises projecting the liquid in a flowing stream, adding abrasive to the stream to mix therewith, thereafter adding air to the stream at its periphery, and maintaining the stream and added air confined for a limited distance after the addition of air to the stream.

2. The method of projecting abrasive material with liquid which comprises projecting the liquid in a flowing stream, adding abrasive to the stream to mix therewith, projecting the stream through an enlarged space containing air at substantially atmospheric pressure so that the stream will entrain air from the space, and confining the stream and entrained air for a limited distance posterior to said space.

3. The method of projecting liquid in a substantially unbroken jet which comprises projecting the liquid in a high velocity jet, adding air to the periphery of the jet adjacent to its point of projection, and maintaining the jet and added air confined for a limited distance after the addition of air to the jet.

ROY L. LUCE.

REFERENCES CITED The following references are of record in the