US2681830A

US2681830A - Nozzle

Info

Publication number: US2681830A
Application number: US268875A
Authority: US
Inventors: Earl A Peterman
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-01-29
Filing date: 1952-01-29
Publication date: 1954-06-22
Anticipated expiration: 1971-06-22

Description

Jun 22, 1954 E. A. PETERMAN NOZZLE Filed Jan. 29, 1952 IN V EN TOR. 15 477 /7 7 e 7771471.

rr farm [K9 Patented June 22, 1954 UNITED STATES PATENT OFFICE NOZZLE Earl A. Peterman, Detroit, Mich. Application January 29, 1952, Serial No. 268,875

5 Claims.

This invention relates to nozzle constructions, and more particularly to high pressure solid stream water nozzles adapted for use with fire apparatus and the like.

A disadvantage of solid stream fire nozzles in the past has been that of limited capacity; that is, the delivery characteristics of the nozzles have not been suflicient to fully utilize the available pumping pressures at the delivery point. This has resulted in decreased efiiciency of fire-fighting apparatus, and moreover, improvements in pump design have been hampered by the lack of satisfactory nozzle constructions to carry the higher pressures and therefore test the improved characteristics of the pumps.

It is an object of the present invention to overcome the disadvantages of previously known fire nozzles and to provide a nozzle construction in which higher delivery pressures are obtainable without a corresponding decrease in the quality or range of the solid stream.

It is another object to provide an improved nozzle of the above nature in which a solid stream is available and in Which the higher pressures will activate means for imposing additional restraining factors on the stream surface, thereby maintainin the solidity of the stream as the pressure is increased.

It is also an object to provide an improved nozzle as described above in which the stream is encased in a sheath of air as it leaves the nozzle tip, this air sheath moving at approximately the same rate as the fluid and serving to prevent any fluid turbulence causing fluid particles to leave the stream surface.

It is a further object to provide an improved nozzle construction in which the above characteristics are combined with other nozzle features insuring laminar flow of the fluid so that the stream reaching the nozzle tip will have a minimum of nonaxial flow tending to disturb the solidity of the stream.

Other objects, features, and advantages of the present invention will become apparent from the subsequent description, taken in conjunction with the accompanying drawings.

In the drawings:

Figure l is a side elevational view in cross-section showing thefeatures of the improved nozzle and the air shield at the nozzle tip;

Figure 2 is an end elevational View of the rear portion of the nozzle showing the spacing of the fluid. vanes; and

Figure 3 is an end elevational view of the tip end of the nozzle showing the spacing of the air vanes. if

The nozzle comprises a rearbody section ll and a front body section 12 which are connected by a solder joint 13. It will be understood that although the nozzle body is shown as constructed of two pieces, it could as well be made in a Single solid piece if desired. The rear body section H is provided at its rear end with an adapter memher it. secured to the body member by a threaded connection 55 and seal IS. The rear body section I i may also be provided with a pair of handles i1 for manual control of a nozzle. At the forward end of front body section I2 is a nozzle tip section is secured to section I2 by a threaded connection 19.

The interiors of body sections H and I 2 are provided with a plurality of fluid vanes 2| which extend axially through both body sections and are radially disposed and joined at a common center 22. The outer edges of these vanes are disposed in grooves 23 in the inner surfaces of the body section walls so that the vanes are rigidly held against movement. The vane areas conform to the progressive cross-sectional areas of the nozzle body sections, and in particular it will be noted that the rear body section I I is of a constant diameter, whereas the front section [2 has a gradual taper, narrowin toward the tip. In the illustrated embodiment four such vanes 2| are shown spaced ninety degrees apart, but it will be understood that a different number of vanes could be used without departing from the principles of the invention. The vanes extend from a point adjacent the threaded connection l5 between adapter i l and rear section II to the threaded connection is between the ti I 8 and forward section !2. The rear edges 24 of the vanes are shown as normal to the nozzle axis, but the forward edges 25 are preferably flared so that the change in cross-sectional area as the fluid leaves the vanes will be gradual.

The nozzle tip [3 has in its rear portion a tapered bore 26 contiguous with the tapered bore of forward body section !2. However, the major portion of tip is has a bore 27 of constant diameter so that laminar flow will be further sustained as the fluid leaves the nozzle. The nozzle tip is provided with a circular air shield 23 which is spaced outwardly from the tip and is concentric therewith. This shield comprises an annular wall which in the illustrated embodiment tapers gradually inwardly toward the forward end of the tip, and may be provided with a rear protective ridge 29 and a thickened forward section 3! for reinforcing purposes. The shield is secured to the nozzle tip by means of a plurality of elements 32 which serve as combined supportin ribs and air vanes. These walls, which in the illustrated embodiment are three in number, are equidisa rear edge of the shield and the discharge.

It will be observed that the portions 35 of the vanes 32 which are forward of the nozzle discharge edge 34 are flared outwardly toward the shield so that these vanes blend into the forward edge 35 of the shield. The portions 35 of the vanes are also preferably of progressively decreasing cross-sectional area; that is, the wall thickness gradually decreases toward the forward end as shown best in Fig. 3. Although three equidistantly spaced vanes 32 are shown in the illustrated embodiment, it will be understood that a different number of vanes could be used within the principles of the invention.

In operation, the fluid flowing into the intake end of the nozzle from the hose will normally have a substantial amount of turbulence due to the high rate of flow and the characteristics of the hose wall. As the fluid passes through the adapter I4 into the rear body section II, it will flow between vanes 2| which will tend to increase the laminar flow properties. As the cross-sectional area decreases in the tapered forward section 12 the rate of flow will increase, and the fluid will leave vanes 2i across their flared edges 25. This will mean a gradual change in the cross-sectional, area, minimizing the possibility of turbulence at this point, and the straight section 21 of the nozzle tip l8 will further enhance the laminar properties of the fluid.

As the fluid leaves the discharge edge 3 of the nozzle tip the outer surface of the stream will, through its frictional effect on the surrounding atmosphere, create an air movement in the same direction, and thus a partial vacuum will be formed in the vicinity of edge 34. The air to replace that which is displaced will come from the area directly to the rear of edge 34, namely the air within shield 28. It will be seen that the air flow is restricted by the shield 28 to a direction substantially parallel with the stream travel and that no air currents in a lateral direction will be allowed to occur. This is to be contrasted with the action which takes place at the discharge point of a conventional nozzle tip wherein the partial vacuum created by the entrained air will cause cross currents of air to develop, infiltrating the stream and causing dispersion and turbulence on the outer surface, of the stream. In the improved construction these cross currents cannot occur and as a result the air will form a sheath surrounding the stream and insuring its solidity.

The air flowing within shield 28 will enter the shield from its rear edge 29 and the gradually decreasing shield diameter will cause an increase in the rate of flow of the air stream as it approaches the discharge edge 33. At the same time the presence of vanes 32 will prevent any circumferential movement of the air stream and restrain it to a path of travel parallel to the nozzle axis. When the air stream reaches the discharge edge 34 it will already have a substantial rate of flow and will readily follow and encase the fluid stream. As the air sheath passes the discharge point it will be carried across the narrowing portions 36 of shields 32 so that the gradual change of cross-sectional area will cause a minimum of turbulence. It will be noted that should the rate of flow of the fluid stream be increased, the greater frictional effect on the surrounding air will cause a more rapid rate of air flow from the shield, so that the device will automatically operate to provide increased air sheath protection.

While it will be apparent that the preferred embodiment of the invention herein disclosed is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

I claim: 7

1. In a nozzle, a body section adapted to be connected to a source of fluid under pressure, said body section having a portion of gradually decreasing cross-sectional area, a tip section at the forward end of said body section, a major portion of said tip section being of constant cross-sectional area substantially equal to the minimum body section area, and an annular air shield spaced outwardly from said tip section and concentric therewith, the rear edge of said shield being spaced rearwardly of the tip discharge edge and spaced outwardly of said tip to provide for air entrance in a direction parallel to the nozzle axis, the forward edge of said shield being spaced forwardly of said discharge edge.

2. In a nozzle, a body section adapted to be connected to a source of fluid under pressure, said body section having a portion of gradually decreasing cross-sectional area, a plurality of axially extending fluid vanes within said body section, the forward edges of said vanes being fiared'forwardly and outwardly toward the body section wall, a tip section at the forward end of said body section, a major portion of said tip section being of constant cross-sectional area substantially equal to the minimum body section area, an annular air shield surrounding said tip section and in spaced relation therewith, the rear edge of said shield being spaced rearwardly of the discharge edge of said nozzle tip, the forward edge of said shield being spaced forwardly of said discharge edge, and a plurality of axially extending air vanes between said shield and the nozzle tip.

3. The combination according to claim 1, further provided with a plurality of axially extending fluid vanes within said body section.

4. The combination according to claim '1, further provided with a plurality of axially extending air vanes between said shield and said nozzle tip.

5. The combination according to claim 1, said shield tapering gradually inwardly from its rear edge toward its forward edge.

References Cited in the file of this patent France z Mar. 10,1941