US 2635920 A
Description (OCR text may contain errors)
April 21, 1953 w. E. BOYCE 2,635,920
SPRAY APPLICATOR Filed Aug. 2, 1949 5 Sheets-Sheet l April 1953 w. E. BOYCE 2,635,920
SPRAY APPLICATOR Filed Aug. 2, 1949 5 Sheets-Sheet 3 65 aria INVENTOR. M399 BY: I
April 21, 1953 w, E B C 2,635,920
SPRAY APPLICATOR Filed Aug. 2, 1949 5 Sheets-Sheet 4 V I INVENTOR.
April 1953 w. E. BOYCE 2,635,920
SPRAY APPLICATOR Filed Aug. 2, 1949 5 Sheets-Sheet 5 INVENTOR.
Patented Apr. 21, 1953 UNITED STATES PATENT OFFICE 6 Claims.
This invention relates to a spray applicator for applying any desired type of liquid spray (for example, an insecticide spray) to foliage such as trees in an orchard.
In order to reach the top branches of relatively large trees, the spray must be projected to a relatively great height above the. ground. In conventional spraying apparatus, theheight which the spray will attain is dependent in large measure upon the velocity of the liquid stream as it leaves the spray nozzle, and this in turn is dependent largely upon the liquid pressure employed in driving the spray liquid through the spray nozzle. To attain the high velocity necessary for high travel of the spray, requires relatively great liquid pressures, which in turn requires heavy and expensive pumping equipment which is hard to maintain in efficient working order.
To overcome the need for high pressure pumping equipment, it has heretofore been proposed to have the liquid leave the spray nozzle at a lower and more easily attained pressure, and to waft the liquid mist or spray onto the foliage by a strong blast or current of air. It is to apparatus of this kind that the present invention relates. The air blast or air current type of spray applicator, as heretofore known, has not been entirely satisfactory, for various reasons. An object of the present invention is to provide generally improved and more satisfactory spray applicator mechanism of the air blast or air current type.
Another object is the provision of a spray applicator which is easier to control and manipulate, and more stable in operation, than prior apparatus of this same general type.
More particularly, it is an object of the present invention to provide a spray applicator which will project the spray through a greater distance than is possible with prior applicators of equal size and weight; which will control the spread of the spray more narrowly and place the spray more accurately than prior applicators of comparable size; which will have no appreciable tendency to shift its direction or position in an undesired manner during operation; which is inexpensive to manufacture and easy to maintain or service; and which is well adapted to use with either regular conventional spray mixtures or concentrated spray mixtures, regardless of the pressures employed.
These and other desirable objects are accomplished by the construction disclosed as an illustrative embodiment of the invention in the following description and in the accompanying drawings forming a part hereof, in which:
Fig. 1 is a side elevation of the major parts of a spray applicator rig in accordance with the present invention, with parts broken away and parts in section, and with the applicator itself turned to face in a direction away from the observer, so that the applicator itself is seen in rear elevation;
Fig. 2 is a front elevation of the applicator itself, showing also certain adjacent parts of the spray rig;
Fig. 3 is a horizontal section taken substantially on the line 33 of Fig. 2;
Fig. 4 is a horizontal section taken substantially on the line 4-4 of Fig. 2;
Fig. 5 is a side or edge elevation of the spray applicator itself, with the supporting part or platform of the rig shown in rear elevation;
Fig. 6 is a vertical section taken axially through one of the horizontal trunnions of the applicator, substantially on the line 6-6 of Fig. 5;
Fig. 7 is a horizontal section taken substan tially centrally or axially through the spray applicator drum;
Fig. 8 is a side elevation of part of the structure shown in Fig. 5 on a larger scale, with certain of the trunnion parts shown in vertical section;
Fig. 9 is a view similar to Fig. 5, showing the applicator turned on its horizontal trunnions so as to tilt or point upwardly;
Fig. 10 is a plan of a portion of the spray rig which supports the applicator, with the applicator itself removed in order to show the mechanism beneath; and
Fig. 11 is a vertical section taken substantially on the line I ill of Fig. 9.
The same reference numerals throughout the several views indicate the same parts.
Referring first to Fig. l, the apparatus of the present invention includes in general a suitable vehicle such as a trailer or semi-trailer adapted to be drawn by a tractor or other suitable motive power through an orchard or other place where the spray is to be applied to the foliage. A truck or other vehicle having its own motive power may be used if desired, of course, although it is usually preferred to use a trailer or semi-trailer. Longitudinal frame members of the vehicle are indicated at 2|] and 2!, and are supported by one or more pairs of road wheels 23. The frame supports a tank 25 for containing the spray liquid 21, and it carries also a suitable pump and compressor unit indicated diagrammatically 3 at 29, driven by its own independent motor (not shown), and a fluid pressure receiver or storage tank 3|.
Near its rear end, the frame 2| includes a pair of cross members 35 and 31 (Figs. and 11) supporting a strong fiat plate 39 on which is mounted what may be termed a turret or turntable rotatable about a vertical axis. A bearing housing 41 is bolted or otherwise suitably secured to the plate 39, and this bearing housing carries upper and lower roller bearings 43 and 45, respectively, which form bearings for the hollow shaft or pintle or trunnion 4'! arranged vertically and constituting the axle of the turntable or turret. Supported on this vertical shaft 41 and fixed thereto to rotate therewith are a cable drum 5|, a spacing member 53, and an approximately semi-circular yoke 55, extending laterally and upwardly on a curve as indicated in Figs. 1 and 3, for example. The yoke is formed from a member which is channel shaped in cross section, as will be seen from Fig. 5, and the plane of the yoke is slightly tilted relative to the axis of the vertical shaft 41 so that the upper ends of the yoke arms are offset rearwardly relative to the axis of the shaft 41.
Near the upper ends of the arms of the yoke 55 there are horizontal pivots or trunnions indicated in general and diagrammatically at 57. Mounted for oscillation on these trunnions 5'5 there is a cylindrical casing 59 formed of sheet metalexc'ept for suitable strengthening and reinforcing bands, such as the heavy central channel band 5| (Figs. 5 and 7) to which the truni nions are secured, and the lighter channel bands 63 and 55 at the front and rear ends of the casing. This cylindrical casing may be conveniently referred to as a barrel or drum or shell. It is open at both ends, but has a strong wire mesh screen 6'! across its rear end as seen in Figs. 5 and 7, this protecting screen 57 preferably being dished outwardly 0r rearwardly at its center, as seen in the drawings.
Located approximately centrally within the drum or barrel 59, and supported by suitable upright posts ll and lateral tie rods 73, is a motor indicated diagrammatically at E5, of the internal combustion engine type, preferably an airplane motor'of about 50- horse power rating, of a kind commonly used in light airplanes, such a motor being very suitable for present purposes because it is air cooled, is relatively light in weight, and is available at reasonable cost because it is built in quantity for use in light planes, rather than having to be built specially for purposes of the present spray applicator. This motor is arranged with its crankshaft coincident with the axis of the cylinder or drum as. Mounted on the crankshaft immediately in front of the motor '15, and fixed to the crankshaft in the same manner as the conventional airplane propeller of a light plane, is a propeller Ti which, however, is not a standard airplane propeller, but is a special impeller blade with cut off or squared ends as well seen in Fig. 2. Moreover, the pitch of this propeller is reversed as compared with the pitch of a conventional airplane propeller, so that when the motor 75 rotates in the conventional direction, counterclockwise when viewed from the front as in Fig. 2, or clockwise when viewed from the rear as in Fig. l, the propeller blade will push a stream of air forwardly instead of pulling a stream of air rearwardly. The diameter of the propeller 77 is only slightly less than that of the shell 59, the ends of the propeller blades coming quite close to the wall of the shell.
The motor '55 is supplied with gasoline or other suitable fuel from a pair of fuel tanks 79 mounted externally on the drum 59 on opposite sides thereof above the center thereof. Each of these fuel tanks extends approximately the full length of the drum as seen in Fig. 5, and each is of curved cross section as seen in Figs. 1 and 2, to fit fairly snugly against the circumference of the drum 59 or the strengthening ribs or rings thereon. Each tank is provided with a filling opening and cap 8|, preferably near the forward upper corner of the tank so that when the forward end of the drum is tilted upwardly (as in Fig. 9) to direct the spray upwardly onto foliage above it, no fuel will escape through the filling opening even though there may be an air inlet vent in the filling cap BI.
The motor is also provided with a suitable throttle valve, ignition switch, and other usual control equipment (not shown) of conventional kind as customarily used with aircraft motors of this type.
As will be surmised from what has beensaid above, when the motor 15 is in operation, the propeller ll creates a strong blast or draft of air entering the rear end of the drum or barrel 59 through the protecting screen 6?, thence passing forwardly past the motor 15 and producing the necessary cooling action on this motor, thence issuing past the propeller 11 and out of the forward end of the drum or barrel 59. It is a very strong and powerful blast of air, somewhat similar to the propeller wash of a light airplane employing a comparable 50 horse power motor, but even stronger and more powerful than the propeller wash of such a plane, because the present air stream is confined and controlled by the drum or barrel 59 and hence is more concentrated throughout a limited area thanrthe propeller wash of a plane, which has no such confinement. The forward air thrust of the propeller produces a corresponding rearward thrust on the motor i5, which rearward thrust is transmitted through the mounting bars H and E3 to the shell or drum es and the trunnions 51 thereof. But because the trunnions 5? are offset rearwardly behind the vertical rotary axle 41, the rearward thrust has no tendency to turn the turret on its vertical axis, and the mechanism is quite stable in operation, tending to maintain the position in which it has been set, although being easily shiftable to a different position when desired.
Although the propeller H is in front of the motor l5, it is still a little to the rear of the front face of the drum 59, as seen in Fig. 7. In front of the propeller fl and just a little behind the front face of the drum 59, is a liquid conduit which may be termed a manifold 85, of approximately circular outline as seen in Fig. 2, and of a diameter somewhat less than that of the drum 59. Mounted on and projecting forwardly from this manifold are a great multiplicity of spray nozzles 81, located relatively close to each other, there being approximately forty of such spray nozzles in the preferred construction. Each spray nozzle itself may be of conventional construction, adapted to produce and emit a relatively fine mist or spray of liquid when liquid under suitable pressure is introduced into the conduit or manifold 85.
The preferred arrangement for supplying the spraying liquid t6 the manifold 85 and spray nozzles 81, is as follows: Referring to Fig. l, the pump 29 pumps the spray liquid 21 from the tank through a supply pipe 9| extending along the frame 2| of the rig to a point opposite the vertical shaft 41. The supply pipe then turns downwardly as at 93 (Fig. 5) to clear the frame 2| and then laterally inwardly as at 95 to a position directly below and in axial alinement with the hollow turntable shaft 41, whence the pipe turns upwardly at 91 through the hollow shaft 41. The upper end of this pipe 9'! is squared off at 99 (Fig. 11) and abuts against the lower end of another pipe IUI extending upwardly in axial alinement with the pipe 91. A gland nut I93 threaded into the upper end of the hollow shaft 41 surrounds the pipe IOI and, when screwed tight, serves to compress the packing I95 which surrounds both pipes 91 and IIlI where they abut against each other, thus forming a stufling box which maintains a leak-proof joint notwithstanding the fact that the pipe 91 remains stationary while the pipe IIlI turns with the turret or turntable and its shaft 41.
From the pipe II, a suitable conduit connection, such as the hose IIJ'I, leads upone side of the yoke 55, in the hollow space within this yoke (which is channel-shaped in cross section) to a suitable slot I99 (Fig. 8) where the conduit passes through the yoke to the outside thereof and goes on upwardly to a pipe III (Figs. 2 and 6) which is axially alined with one of the trunnions of the drum 55, and which passes through a gland nut H3 screwed into the rotatable part of the trunnion. This pipe III is in abutting relation to an axially alined pipe I I5 which turns with the barrel or drum 59 when the latter turns on its trunnions, whereas the pipe III remains stationary or substantially stationary, although it may turn a little within the limits of the flexible conduit IIlI. Packing III, compressed by the gland nut H3, surrounds the ends of both pipes III and H5 where they abut each other, thus forming a stuffing box or gland to maintain a liquid tight joint at this point.
From the pipe H5, suitable piping extends to the manifold 85, this piping preferably being led along the outside of the drum 59, in order to avoid interference with the rotating propeller 11. For example, as best seen in Fig. 7, the pipe H5 is connected to a pipe |2| which extends obliquely far enough to clear the main supporting and reinforcing band SI of the drum 59, then leads to a radial pipe I23 which goes through the wall of the drum, which in turn leads to a pipe I25 extending axially outside the wall of the drum, past the plane of rotation of the propeller I1, and then a pipe I21 leads radially inwardly through the drum from the pipe I25 to a T-connection with the manifold 85. Suitable elbows, couplings, unions, and other appropriate pipe fittings are used at various places in the piping, as seen in the drawings, but it is thought unnecessary to describe them specifically.
Since the current of air produced by the propeller TI is relied upon for carrying the spray to the foliage which is to be treated therewith, rather than the velocity of the spray liquid as it issues from the nozzle, the pump 29 need not be a high pressure pump but may be a liquid pump of the medium or low pressure variety, producing only enough pressure to insure the necessary spraying effect as the liquid leaves the spray nozzles. This results in a great saving both in initial cost and in maintenance cost of the pumping equipment.
The attendant who controls the operation of the spray applicator rides on a suitable seat (not shown) near the forward end of the rig, ahead of the tank 25, so that he will be fairly close to the driver of the truck or tractor and can verbally give any necessary instructions to such driver, as may be necessary from time to time as the spraying operation continues. From such seat ahead of the tank '25, the operator controls the rotary movements of the spray applicator about its vertical axis by means of a hand wheel |3I (Fig. l) the shaft I33 of which is connected, through a universal joint I35, to a bevel pinion I3! meshing with a bevel gear I39 on a vertical shaft I4I, the lower end of which shaft carries a cable drum or pulley I43 (Figs. 1 and 10) around which is wrapped a cable I45 which extends to and is also wrapped around the cable drum 5| which is fixed to the turntable shaft 41. The diameter of the cable drum I43 is less than that of the cable drum 5|, and the diameter of the bevel pinion I3'I is less than that of the bevel gear I39, so that the parts act as a reducing gear permitting easy and close adjustment of the horizontal rotative direction or azimuth of the turntable by means of the hand wheel I3I.
For tilting the drum in altitude, on its horizontal trunnions, fluid pressure means is preferably employed. Such fluid pressure means may be either liquid (i. e., a hydraulic control system) of gas, such as compressed air or vacuum. Conveniently, gas pressure stored in the receiver or tank 3|, controlled by a three-way valve I51 readily accessible to the operator, is admitted into one or the other of the two tubes I53 and I55 which extend from the valve |5I to the turntable, and which have flexible portions of sufficient length to permit the turntable to turn on its vertical pivot to a range of about 300 degrees. It may be mentioned here that it is not necessary that the turntable be capable of turning through a complete circle of 360 degrees,
because there is no object in having the drum pointed straight forwardly, since the tank 25 would interfere with proper delivery of the spray-carrying air blast and also the operator would be in the line of the air blast. So a rotation of about 300 degrees or even a little less than this is amply sufficient for all practical purposes, and flexible portions of the small light fluid pressure lines I53 and I55 are sufficient to permit this amount of turning, without the necessity of employing glands or stuffing boxes. In fact, it would even be possible to employ flexible hose connections for supplying the spray liquid to the manifold 85, without the use of stuffing boxes or glands, but it is more convenient and practical to use the gland or stuffing box arrangements above disclosed, because the supply line for the spray liquid must be considerably larger and of greater capacity than the small pressure lines i233 and I55.
These fluid pressure supply lines I53 and I55 enter the yoke 55 near the bottom thereof and pass upwardly in the hollow space within the yoke arm, emerging through holes I5! and I59, respectively (Figs. 5 and 8), whence the fluid pressure lines I53 and I55 are connected respectively to the top and bottom of a fluid pressure cylinder I6I, the lower end of which is pivoted at I63 to a bracket I65 fixed on the yoke 55. The cylinder I6I contains a piston having a piston rod IH extendingout through the. upper: end of the cylinder and pivoted at. I13 to an arm ll fixeclto the drum 59, conveniently by being fixed to the supporting ring 6.! thereof.
When the control valve 15! is turned to admitpressure to the line I53 leading to the upper end of the cylinder lti, and to relieve. pressure from the other line I55 leading to the lower end of a the cylinder, the piston: in this cylinder will move downwardly and the piston rod ill willpull downwardly on the arm 5.75, thus causing the drum 69 to tilt upwardly or swing. in. altitude, from a position such asshown in. Fig. 5* to some such position as shown in Fig. 9. The degree of altitude or upward tilt may, of course, be varied as desired by proper manipulation of. the valve 151. When the-valve reverses the fluid pressure connections, the piston rod I'll; is moved upwardly and the drum is tilted back. down to an approximately horizontal position; The horizontal position is the lowest position of the. drum, there being no occasion for having it tilt. downwardly', since the appliance ismounted at a fairly low elevation and allof the foliage to be treated is at or above the height of the drum.
Approximately in the plane of the front face of the drum, strong metal bars extend diametrically, one bar it! being on the vertical diameter of the drum, and the other bar 183 being onthe horizontal diameter, both bars having their ends firmly fixed to the drum. These bars, as seen in Fig. "I, are thin in one cross sectional dimension, and have their thin edges presented axially to the drum, so as to give but little in.-
terference to the air blast. Where these two diametrical bars intersect, a bearing is formed, and in thisbearing is rotatably mounted a stub shaft I85 axially alined with the crankshaft of the motor 15, the stub shaft I85 having a cross pin H31" near its inner end, and having. a spring H39 in front of the bars I!!! and it? to tend to move the shaft 185 axially forwardly. The front end of'the shaft IE5 has a socket for receiving a suitable crank for use in starting the motor. When the crank is inserted in the socket and. the shaft |85 is pushed rearwardly against the force of. its light spring I89, the cross pin i3! is clutched with suitable-clutch teeth formed on the propeller hub. Then the crank is turned to start the motor. When the motor starts, the shaft E85 moves forwardly and the spring i89 holds it in the forward position, wherein the cross pin ill! is unclutched from the clutch. teeth on the; propeller hub.
In addition to supporting the cranking shaft [85, the di'ametrical bars I8! and I83 also serve the function of supporting the manifold 85 in proper position. As seen in Fig. 3, the plane of the manifold 85 is immediately behind the plane of the bars [ill and. I83, so that the manifold 1 85 lies against the rear edges of the bars l8! and I183: where the latter cross the manifold, and the manifold is held to the bars at the crossing pointsby U-bolts I95 having clamping nuts till thereon.
It is found that best results are attained if theaxial length of the shell or drum 59 is at least half the diameter thereof, and preferably a little more than half the diameter. If a shorter axial length is employed, there is not sufficient directional control of the. air blast to concentrate it in a manner to give itsufiicient range and carrying power. It is also preferable to place the manifold and the spray nozzles rather close to the front end. of the drum, the spray nozzles 8 in the preferred. construction having: their heads practically flush with thefront end of the drum. and the. propeller TI being only slightly behind thespray nozzles.
Another feature of the invention is the fact that azvery large number of spray nozzlesare used in close proximity to each other. and that the ring or circleof spray nozzles is located. at a. distance from about two-thirds of. the way to: about. three-quarters of. the way outwardly from. the. axial center toward the periphery of the drum. By thus locating the spraynozzles about two-thirdsto three-quarters of the way fromthe center to the periphery ofthe drum, they are located inwhat seems to bentheposition of greatest velocity of the air blast produced by the: propeller, and very great covering power and carryingpower are attained. In the form of construction shown in Fig. 2, it is seen that the diameter of. the-manifold is approximately seven-tenths of'the diameterof the shell or drum 59.
Excellent results have been attained by using a shell with a diameter of about 51 inches, and
an. axial length of about 28 inches, the manifold ring having a diameter of about 36 inches and carrying. approximately forty spray nozzles, spaced approximately evenly around the circumference of the manifold. ring. Therearwardoifset of the axis of the horizontal trunnions 5:1, behind the axis of the verticaltrunnion or shaft 41, is approximately 5- inches. These dimensions are given only as an illustrative example. of one construction which has proven particularly satisfactory, and are not intended to be taken in a limiting sense.
As the rig is drawn through the orchard. or past the other foliage which is tobe treated, with the motor 15 running and with the spraying liquid being supplied to the. manifold 8.5 and issuing from the spray nozzles 37, the strong and concentrated blast of air from the propeller ll will carry the spray onto thefol'iage, the exact direction of the spray both in azimuth and in altitude being readily controlled bythe operator by means or the hand wheel 13! and-the control valve l5l, respectively.
To secure a sufficiently strong blast of air to attain maximum efficiency and range-of the apparatus, the motor should have a power of :about fifty horsepower if the drum diameter is about fifty-one inches, as stated in the foregoing example, the motor having correspondingly and proportionately greater power if the diameter of the drum is greater. So it may be said that. the motor should have approximately one. horsepower foreach inch of diameter of the drum.
While an. internal combustion engine has been mentioned as the preferred form of motor, it is obviously not the only possible form of motor for driving the propeller. In many cases it may be desirable. to use an electric motor or a hydraulic power motor, operated from an electric power unit or a hydraulic power unit mounted in any convenient near-by, location, such as on the forward part of. the rig.
It is. seen. from the foregoing disclosure that the above mentioned objects of theinvention are admirably fulfilled. It is. to be understood that the foregoing disclosure is given by way of illustrati-ve example. only, rather than by way of limitation, and. that without. departing from the invention,the details maybe. varied within. the scope of the appended claims.
What is claimed is:
1. A spray applicator including a support, a turntable mounted on said support for rotation about an approximately vertical axis, a substantially cylindrical drum entirely open and unobstructed at its rear end mounted on said turntable for rotation about an approximately horizontal axis extending approximately diametrically through said drum, an internal combustion motor mounted in said drum in spaced relationship to all of its walls, a propeller mounted in said drum near the forward end thereof and connected to said motor to be driven thereby for rotation about a rotary axis approximately coinciding with the cylindrical axis of the drum, to draw a blast of air in the rear end of said drum past said motor and thence to expel it from the front end of said drum, a multiplicity of widely distributed spray nozzles mounted in said drum near the front end thereof forwardly of the plane of rotation of said propeller and constituting the only obstruction forwardly of the latter to a blast of air issuing therefrom, and means for supplying liquid to said spray nozzles to issue therefrom in a spray in the path of travel of said blast of air so that said blast of air will impel said spray for a substantial distance forwardly from said drum.
2. A construction as described in claim 1, further including a fuel tank mounted directly on the outside of said drum out of alinement with the air blast for supplying fuel to said internal combustion motor.
3. A construction as described in claim 1, in which said approximately horizontal axis is central with respect to the motor and is offset rearwardly behind said approximately vertical axis in a direction rearwardly of the air delivery end of the drum.
4. A construction as described in claim 1, in which said spray nozzles are arranged at the top, bottom and sides of the delivery end of said drum and approximately flush therewith but housed. and protected thereby.
5. A construction as described in claim 1, further including a hollow shaft extending along said approximately vertical axis for supporting said turntable, said means for supplying liquid tosaid spray nozzles including a supply conduit extending axially through said hollow shaft.
6. A construction as described in claim 1, further including a hollow trunnion extending along said approximately horizontal axis for supporting in part said drum for said turntable, said means for supplying liquid to said spray nozzles including a supply conduit extending axially through said hollow trunnion.
WILLIAM E. BOYCE.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,864,198 Johnson June 21, 1932 2,220,082 Daugherty Nov. 5, 1940 2,238,120 Launder Apr. 15, 1941 2,454,339 Potts et al. Nov. 23, 1948 2,476,960 Daugherty July 26, 1949 2,515,792 Ofeldt July 18, 1950 2,561,432 Tanter July 24, 1951 2,577,828 Tanter Dec. 11, 1951