Abstract:
An agricultural/viticultural sprayer including a pair of curved arms to partially encircle a row of crops such as vines to be sprayed. Each arm carries a plurality of fan spray heads, and each arm is mounted on a support arm rotatable about a vertical pivot, whereby each of the curved arms can be rotated from a transport position to a spread operating position while remaining symmetrical about a plane generally normal to the path of travel when in use.

Description:
FIELD OF THE INVENTION 
     This invention relates to crop spraying and more particularly to machine especially suited for spraying agricultural chemicals in vineyards and orchards. 
     BACKGROUND OF THE INVENTION 
     The spraying of agricultural chemicals in orchards and vineyards utilizing vehicle mounted air blast sprayers is now a long standing practice. Such air blast sprayers use large volumes of high pressure air, require larger tractors and often, if not universally, disperse excessive quantities of agricultural chemicals. Typically, conventional sprayers can only cover one row at a time. Moreover, prior sprayers are not suited for concurrently applying chemicals to two or more rows of crops when the crops are on sloping ground or terraced land. 
     My U.S. Pat. No. 5,921,019 issued Jul. 13, 1999 discloses and claims a spraying machine which includes at least a pair of curved arms carrying a plurality of fan spray heads. The spray heads are positioned to direct airborne spray material into the canopy of each tree or vine in upward and downward directions simultaneously from both sides of the canopy. While the method and apparatus of my prior patent has enjoyed commercial success and is a very positive advance over the prior art, it was: 
     Relatively expensive to produce a suitable structural frame to support the spray arms; 
     Five fan spray heads per vine row is required when travelling at high ground speed; 
     Generally suitable for large tractor, crop field and large and dense vine canopies; 
     Not well suited for terraced crops; and, 
     Can be difficult to transport to a crop field to be sprayed. 
     SUMMARY OF THE INVENTION 
     In one form of the invention, a pair of masts are mounted on a trailer vehicle. The trailer supports a tank for transporting agricultural chemicals to be applied as well as a motor and pump arrangement for dispensing the chemicals. 
     A pair of support arms are pivotally mounted atop the masts and extend rearwardly. The support arms each carry a pair of curved spray arms. Linkages are provided to rotate the support arms relative to the masts about both horizontal and vertical axes. Other linkages are provided to maintain each pair of spray arms symmetrical about an associated imaginary plane normal to the vehicle&#39;s path of travel when transported and when in use. 
     One support arm is shorter than the other in order that the spray arm pairs may be positioned one behind the other in a transport position. The support arms are rotated about their vertical axes to a use position outboard of the vehicle for use in spraying a field. 
     In order to accommodate sloping and terraced conditions, the support arms are independently pivotable about their respective horizontal axes, such that each pair of spray arms may be positioned at an elevation appropriate for a crop row being sprayed. 
     The spray arms of each pair are relatively movable between a relatively close transport position and a spaced apart use position. Further linkage is provided to shift the spray arms of each pair relatively between the closed transport and spaced use positions. The support mast linkage maintains a perpendicular orientation of the spray arms with respect to a path of travel when the support arms are pivoted about their vertical pivots to move the arms from transport positions with the spray arms one behind the other for transport and outboard straddling different rows of crops when in their use positions. 
     Accordingly, the objects of the invention are to provide a novel and improved spraying machine which is more compact and maneuverable than prior art machines and which is capable of concurrently spraying two or more crop rows which are of different heights. 
     The invention also contemplates variation of the described apparatus having two spray arm pairs to include an apparatus having a single pair of spray arms and a further apparatus supporting three such pairs of spray arms for concurrently applying crop spray to three crop rows. 
     The invention also contemplates an embodiment in which such spray apparatus is mounted on a self propelled vehicle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an elevational view of the apparatus of the present invention utilizing a trailer vehicle and two pairs of spray arms; 
     FIG. 2 is a rear elevational view of the apparatus of FIG. 1; 
     FIG. 3 is an elevational view of a pair of spray arms and supports; 
     FIG. 3 a  is an enlarged fragmentary view of the spray arm support and linkage; 
     FIGS. 4 a  and  4   b  are fragmentary plan views of the mast supported ends of a pair of support arms and the linkage for moving the support arms relative to their supporting masts, while FIG. 4 b  is a fragmentary elevational view thereof; 
     FIG. 5 is a top plan view of the apparatus of FIGS. 1 and 2 with the arms in their transport positions; 
     FIG. 6 is a top plan view on a reduced scale of the apparatus of FIG. 5 with the arms positioned in their use positions; 
     FIG. 7 is a rear elevational view of the apparatus of FIG. 6; 
     FIG. 7 a  corresponds to FIG. 7, while illustrating the pairs of spray arms positioned at different elevations; 
     FIG. 8 is a side elevational view of a self propelled version of the apparatus of this invention; 
     FIG. 8 a  is a rear elevational view of the apparatus of FIG. 8 with the spray arms in their use positions; 
     FIG. 9 is a top plan view of a version of the present invention utilizing three pairs of spray arms; 
     FIG. 9 a  is a rear elevational view of the device of FIG. 9; and, 
     FIG. 10 is a side elevational view of a self propelled version of the present invention utilizing three pairs of spray arms. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings and to FIGS. 1-4 in particular, a trailer T is shown. The trailer includes a tank  1  for carrying a supply of agricultural chemicals. The tank is supported on a frame  2 . The trailer T is mounted on wheels  3  for transport through a vineyard or orchard being sprayed. 
     The trailer includes a drawbar  4  for coupling to a pulling vehicle such as a tractor. A pump  5  is mounted on the frame  2  for withdrawing chemicals from the tank  1 . Chemicals are transported through conduits not shown to fan type spray heads  6 , 7 . The spray heads are driven by a prime mover  8  which may be either an alternator or a hydraulic pump. The prime mover  8  is powered by the pulling vehicle through a power take-off  9 . A control system  10  is provided to control the delivery of power and chemicals to the fans in a known manner. 
     A pair of masts  11 , 12  are vertically mounted on the trailer. A pair of elongate, generally horizontal, support arms  13 , 14  are respectively pivotally mounted on the masts  11 , 12 . A pivot  15  supports a pair of curved spray arms  16  at an outboard or rear end of the masts  13 . A pivot  17  supports a corresponding pair of curved spray arms  18  at an outboard or rear end of the mast  14 . 
     A linkage is interposed between the support arms  13 , 14  and the masts  11 , 12  for swinging the support arms relative to the masts about horizontal pivots. The linkage includes a bracket  19  secured to the support arm  14  and a further bracket  20  secured to the support arm  13 . A link  21  interconnects the brackets  19 , 20 . A cylinder  22  is connected to the bracket  19  and a frame member  23  interposed between and connected to the masts  11 , 12 . An examination of FIGS. 4 and 4 a  will show that on extension of the cylinder  22 , the support arms  13 , 14  are moved from the transport position of FIG. 4 to the use position of FIG. 4 a . Conversely, contraction of the cylinder  22  will shift the support arms  13 , 14  from the use position of FIG. 4 a  to the transport position of FIG.  4 . 
     A cylinder  24  is interposed between and connected to the mast  11  and the support arm  13 . Similarly, a cylinder  25  is interposed between and connected to the mast  12  and the support arm  14 . The cylinders  24 ,  25  have extended rods respectively pivotally connected to the support arms  13 , 14  at locations A remote from the masts. Actuation of the cylinders  24 , 25  are respectively effective to elevate and lower the masts  13 , 14  by rotation about horizontal pivots P, FIGS. 2 and 4 b.    
     Referring now to FIGS. 3 and 3 a , a spray arm support bracket  26  is supported at an outboard end of the support arm  14  for rotation about a horizontal pivot  26 P. A pair of spray arm brackets  28  are respectively pivotally connected to the support bracket  26  at B. The spray arm brackets  28  each include a sleeve  28   a  in which upper ends of the spray arms  18 , are mounted. Fasteners F extend through apertured end portions of the sleeves  28   a  and thread into the arms  18 . The fasteners F support the arms  18  in the sleeves  28   a  while allowing some rotation of each spray arm should one of the spray arms  18  or the spray heads  6  mounted thereon strike an obstruction as the spray apparatus is being transported. 
     An arm positioning cylinder  27  is interposed between the support arm brackets  28  for moving the arms  18  between their relatively close transport position of FIG.  2  and the use position of FIG.  7 . An identical linkage arrangement is interposed between the pair of spray arms  16  which, since it is identical, will not be described further. 
     The pairs of spray arms  16 , 18  are respectively maintained in an orientation such that each is symmetrical about an imaginary plane normal to the path of vehicle travel when the spray apparatus is in use. FIG. 5 best illustrates the mechanism which maintains this orientation of the spray arm pairs as they are moved between their transport positions as shown in FIG.  5  and the use positions as shown in FIG.  6  through actuation of the cylinder  22 . Adjuster horns  30 , 31  are respectively connected to the spray arm support brackets  26  of the arm pairs  16 , 18 . Cables  32 , 33  respectively extend between the frame member  23  and the adjustor horns  30 , 31 . Springs  34 , 35  respectively extend between the adjustor horns  30 , 31  and the support arms  13 , 14 . As the support arms are moved between the transport position of FIG.  5  and the use position of FIG. 6 the cables  32 , 33  acting against the bias of the springs  34 , 35  cause the respective spray arm pairs to rotate about their vertical pivots  26 P. 
     FIGS. 8 and 8 a  illustrate spray apparatus of the present invention mounted on a tractor  36 . Here a single pair of curved spray arms  37  are mounted on the tractor for spraying a canopy C is illustrated in FIG. 8 a.    
     FIGS. 9 and 10 illustrate the apparatus of the present invention utilizing three pairs of spray arms  43 , 44 , 45 . In FIG. 9 a trailer  38  is provided which is constructed to straddle a center row of three rows of vines, as is best seen in FIG. 9 a . The trailer  38  supports the pair of spray arms  44  while a pair of outrigger arms  39  respectively support the pairs of spray arms  43 , 45  either in the use position shown in FIGS. 9 and 9 a  or a transport position corresponding to the position shown in FIG. 10 where the spray arm pairs  43 , 44 , 45  are mounted on a self propelled vehicle  42 . 
     Operation 
     In operation the drawbar  4  of the trailer T and the power take-off  9  are coupled to a tractor. The tank  1  is filled with chemicals and the trailer is transported to a location such as a vineyard or orchard to be sprayed. During the transport, the arms are in the storage positions shown in FIGS. 2 and 5. The cylinder  22  is actuated to move the support and spray arms from their transport positions to their use positions as shown in FIG.  7 . To position the spray arms at heights appropriate for the size of the plants to be sprayed and to adjust for uneven terrain, where the terrain is uneven, the cylinders  24  and  25  are operated to shift the support arms  13 , 14  to appropriate elevations as suggested in FIG. 7 a  the arm positioning cylinders  27  are extended to spread the spray arm pairs into the use positions. Adjustments may be made to the spray arm pairs as to their spacing in the use position according to the sizes of the canopies to be sprayed. 
     The tractor is now driven between rows as suggested in FIGS. 7 and 7 a  as the pump  5  and the prime mover  8  are operated under control of the controller  10 . The pump  5 , through such control, provides appropriate quantities of the chemical to be sprayed to each of the spray heads  6 , 7  while the prime mover  8  drives spray head fans to blow the spray material into the canopy being sprayed in a known manner. 
     Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction, operation and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.