US3393873A - Quick shut-off, low pressure drop spray nozzle - Google Patents

Description

July 23, 1968 w, C, LARSON 3,393,873

QUICK SHUT-OFF, LOW PRESSURE DROP SPRAY NOZZLE Filed Dec. 30, 1965 United States Patent O 3,393,873 QUICK SHUT-OFF, LOW PRESSURE DROP SPRAY NOZZLE William C. Larson, Utica, Mich., assignor to Holley Carburetor Company, Warren, Mich., a corporation of Michigan Filed Dec. 30, 1965, Ser. No. 517,635 3 Claims. (Cl. 239-533) ABSTRACT OF THE DISCLOSURE This application discloses a quick shut-off, low pressure drop nozzle adapted for use in connection with apparatus for spraying fluid herbicides and insecticides, the nozzle including a housing, a long stroke diaphragm movable in the housing and forming a first Iand second chamber therein, the rst chamber being open to the atmosphere, the second chamber having an in let .and outlet, the outlet including a valve seat and nozzle means, a valve plunger attached to the diaphragm for engaging the valve seat, Iand the diaphragm being spring loaded in the valve seating direction.

This invention relates to spray nozzles, and more particularly to a quick shut-01T nozzle particularly adapted for luse in connection with apparatus for spraying fluid herbicides and insecticides.

Application Ser. No. 495,756 entitled Fluid Supply System and led on Sept. 27, 1965, now Patent No. 3,362,643 issued lan. 9, 1968, in the names of William C. Larson and Steven J. Garbarino discloses apparatus for spraying fluids such as those referred to above from a moving vehicle such as a helicopter, for the purpose of destroying vegetation and the like along the rights of way, etc.

It can be seen that the right of way to be sprayed may terminate adjacent a food crop or a golf course on which thefiuids must not be sprayed. Accordingly, the nozzle must be quickly and completely cut off at or near the end of the right of way so that fluid cannot drip, even in minute quantities, onto the restricted area.

While nozzles of this type have been proposed, they are characterized by certain undesirable features, such as reversal of flow within the nozzle resulting in an excessive pressure drop and possible disturbance of the flow pattern of the nozzle. This is particularly so in the ease of nozzles for apparatus such as that disclosed in the above referencedapplication having control of the spray width as a main feature thereof.

Accordingly, an object of the invention is to provide a quick shut-off, minimum pressure drop spray nozzle, particularly suited for use in spray equipment of the type referred to above.

Another object of the invention is to provide a nozzle wherein there is no reversal of the ow through the nozzles Iand wherein the volume of uid downstream of the shut-off valve that cannot be prevented from dripping is minimized.

Another object of the invention is to provide a nozzle having a positive seal against leakage of fluid through the nozzle, even if there is a slight residual pressure in the fluid line leading to the nozzle.

A still further purpose of the invention is to provide a nozzle structure including a long stroke diaphragm operating -a spring-loaded O-ring seal plunger or valve, wherein pressure on the diaphragm moves the plunger away from the nozzle and the `spring force closes the nozzle When the pump for the fluid is shut off.

Another object of the invention is to provide a nozzle having means for connecting `thereto a iiexible uid conduit, this being desirable where the nozzle, or plurality of nozzles, must be moved to control the spray width.

A still further object of the invention is to provide such a nozzle assembly that is relatively simple and inexpensive to manufacture and assemble and that is reliable in operation and easy to maintain.

These and other objects and advantages of the invention will become more 'apparent when reference is made to the following specification and the accompanying drawings wherein:

FIGURE l is a top plan view of a nozzle assembly embodying the invention;

FIGURE 2 is a cross-sectional View taken on the plane of line 2-2 of FIGURE 1 and looking in the direction of the arrows.

Referring now to the drawings in greater detail, it will be seen that the nozzle assembly 10 may comprise an upper portion 12 and a lower portion 14, secured together by any suitable means such as the screws 16. For airborne spray equipment, the nozzle assembly 10 is preferably fabricated from light-weight metal or some suitable plastic that is not corroded by the fluid being sprayed.

The upper portion 12 comprises a substantially cylindrical housing having a bolting flange 18 at the open end thereof, with holes 20 to receive the securing screws 16. Extending from one side of the housing, near the bolting flange 18 end thereof, is a boss 22 which may have formed therein threaded openings 24 to receive bolts by which the nozzle 10 may be secured to a support. The upper end of the housing is formed with an opening 26 to vent the same and with any suitable stop 28 the purpose of which will be explained.

The lower portion 14 of the nozzle 10 is .also substantially cylindrical and provided with bolting ange 30 mating the bolting ange 18 formed on the upper portion 12. The bolting flange end of the portion 14 may have a web 32 extending thereacross, with openings 34 therein providing communication between the upper and lower portions 12 and 14 of the assembly 10. A guide sleeve 36 may extend axially with the portion 14 for a purpose to be described. The other end of the portion 14 is provided with a reduced diameter portion 38, the exterior 40 of which is threaded. A conduit 42 preferably extends angularly from the portion 14, the Vfree end of the conduit 42 having an integral bead 44 over which a flexible conduit -46 may be applied and clamped by means of a wire spring or other retainer 48.

A nozzle tip 50 having an annular radially extending ange 52 intermediate the ends thereof is inserted into the passage 54 through the reduced end 38 of the portion 14, with the flange :52 engaging the free end l56 thereof. A locking nut 58 clamps the nozzle tip 50, which in this particular instance has a discharge opening 60 that extends part way up the side of the tip, in place.

The upper and lower portions 12 and 14 of the nozzle assembly 10 are clamped together, with the outer peripheral edge '62 of a long stroke type diaphragm 64 therebetween. This locks the diaphragm 64 in place and prevents leakage, in the manner of .a gasket. The diaphragm -64 is provided with a central opening 66, and the oppositely disposed washers 68 and the support member 70 also h'aving central openings, through which the threaded end 72 of the plunger or valve stem 74 is inserted. The nut 76 is then tightened on the threaded end 72l of the stem 74 and against the upper washer 68 to secure the stem to the diaphragm.

The other end of the stem 74, in assembly is inserted through passage 54 and the guide sleeve 36, is formed with -a cone valve body 78 having a spring guide 80 and seat 82 on the upper surface thereof and an annular groove 84 in the intermediate porti-on thereof to receive an 3 O-ring seal 86. The coil spring 88 is guided by the outer surface of the stem guide 36 and the other end thereof seats on the web 32 extending across the portion 14.

The nozzle tip 50 is formed with a cone seat 51 at the upper end thereof which the O-ring seal 86 engages when the stem 74 and its plunger 78 are moved t-o their dottedline closed position. It should be noted that the volume of the chamber 53 below the closed plunger 78 is minimized so that the amount of fluid that must drip after the plunger is closed is thereby minimized.

The stop 28 extending inwardly from the upper end of the upper member 12 limits the upward travel of the stem 74 so as to prevent rupture of the diaphragm 64 and the opening 26 vents the chamber above the diaphragm to atmosphere.

OPERATION The nozzle assembly may be attached to a support member in the manner of the valves 12 or 13 disclosed in the above referenced application, Serial No. 495,756. When a pump places the fluid in the flexible conduit 46 under pressure, the pressure acts on the diaphragm 64, lifting the diaphragm and stem 74 to their solid line position in FIGURE 2, against the force of the return spring 88. With the plunger 78 and seal 86 away from the nozzle tip 50, fluid will flow through the nozzle and out the nozzle discharge opening 60 without a reversal in the direction `of flow, and thus with minimum disturbance in the flow pattern. It should be noted that flow from conduit 42 to chamber 53 is essentially straight line flow and plunger 78 is out of the ilow path when the valve is in the full open position. Also, the pressure drop in the nozzle is substantially zero, as compared to some prior art nozzles having a pressure drop of about 5 p.s.i., resulting in maximum efficiency and enabling the use of a smaller pump.

When the end of the arca to be sprayed is approached, the pump is shut olf, at which time the pressure on the diaphragm is eliminated or substantially reduced and the spring 88 moves the stern and plunger 78 downwardly in FIGURE 2, causing the O-ring 86 to seat on the conical inner surface 51 of the nozzle tip 50. This sealing action, in which the O-ring is wedged against the upper edge 90 of the groove 84 and the conical surface 51 results in the immediate stoppage of flow and the complete elimination of any possibility of dripping from the nozzle, except `for the very small volume of fluid below the O-ring seal. Furthermore, when the pump is turned on again, sealing by the O-ring 86 will be maintained until such time as the pressure differential across the diaphragm 64 is suillcient to overcome the force of the spring 88. That is, intermediate pressures not sufllcient to overcome the force of the spring '88 will increase the sealing efficiency of the O-ring 86 due to the pressure differential across the plunger 78.

It should be apparent that the nozzle structure disclosed and described is inexpensive to manufacture and assemble and that it is very ellicient in operation and capable of accomplishing the aforementioned objects of the invention.

While a preferred embodiment of the invention has been shown and described in such detail as to enable anyone skilled in the ar-t to practice the same, modifications thererof may lbe possible, and no limitations are intended except those recited in the appended claims.

What I -olaim as my invention is:

1. A low flow resistance fluid spray nozzle assembly, comprising a housing, a long 'stroke diaphragm movable in said housing and dividing the same into oppositely disposed chambers, one of said chambers being vented to the atmosphere, the other of said chambers having a fluid inlet and a fluid discharge outlet, the axes of said inlet and said outlet having an included angle greater than to minimize changes in direction of flow through said inlet, said other chamber and said outlet, said outlet being formed with a valve seat, said diaphragm having a valve secured thereto and being spring loaded in the valve seating position, and said valve being out of the fluid flow path when in the full open position.

2. A nozzle assembly such as that recited in claim 1, wherein the volume of said outlet downstream of said valve when seated is a fraction of the volume of said other chamber.

3. A fluid spray nozzle assembly; comprising a housing; a long stroke diaphragm movable in said housing and dividing the same into oppositely disposed chambers; one of said chambers being vented to atmosphere, the other of said chambers having a fluid inlet and a fluid discharge outlet; the axes of said inlet and said outlet having an included angle greater than 90 for providing an essentially straight line fluid llow path from said inlet to said outlet; ysaid outlet comprising a reduced annular lportion having external threads, a nozzle tip including a conical valve seat and an external radially extending flange, said tip being inserted into said reduced portion with said flange engaging the free end thereof, said tip being retained in said reduced portion by a nut threaded 0n said external threads and having an inwardly extending portion engaging said flange; said diaphragm having a valve secured thereto for engaging said conical valve seat and being spring loaded in the valve seating direction; said valve comprising a stem attached to the center of said diaphragm at one end thereof, the other end of said stem having a conical valve plunger attached thereto, said conical valve plunger being formed with a groove having an O-ring seal disposed therein for engaging said conical valve seat, said valve plunger and stem being out of the said fluid flow path when said valve is in the full open position.

References Cited UNITED STATES PATENTS 2,639,194 5/1953 Wanna 239-533 2,842,160 s/1958 Rekeaye.

3,102,691 9/1963 Gau 239-583X 2,030,143 2/1936- Giger-Kauai 137-510 FOREIGN PATENTS 161,356 4/1921 GreatBntain. 447,743 3/1935 Great Britain.

M. HENSON WOOD, JR., Primary Examiner.

H. NA'ITER, Assistant Examiner.

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