AU667229B2 - Boom for spraying apparatus - Google Patents

Description

667229 P/00/011 Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Address of Applicant: Actual Inventor: Address for Service: Darryl James MARTIN Unit 1, 209 Chester Pass Road ALBANY W,A. 6330 Darryl James MARTIN GRIFFITH HACK CO, 256 Adelaide Terrace PERTH W.A. 6000 Standard Complete Specification for the invention entitled: BOOM FOR SPRAYING APPARATUS Details of Associated Provisional Applications: PL4393 filed in Australia on August 28, 1992 by D.J. Martin Details of Parent Application for Divisional Applications: The following is a full descriptioi of this invention, including the best method -r--of performing it known to me:- 7L L i; i 2-- BOOM FOR SPRAYING APPARATUS The present invention relates to a boom for spraying apparatus of the kind towed or mounted behind a vehicle for applying chemicals to large areas of land, commonly referred to as boomsprays.

The use of boomsprays on Australian farms is now well established as an efficient and more environmentally acceptable j method of broadacre spraying of pesticides, such as herbicides and insecticides. Much work has been done in improving the design of boomsprays, including the design of pumps and filters, nozzles, markers, chassis, axles and wheels, as well as tne boom itself. A basic boomspray comprises a tank for containing the pesticide, a plurality of spray nozzles mounted on a boom, a pump system for delivering the pesticide to the nozzles and some means for controlling the rate of delivery of r the pesticide to the no'zles. Most boomsprays are also fitted with a marker, such as a foam marker, for accurately marking sprayed areas to ensure that each pass of the boom is correctly aligned with the previous pass. In a well designed boomspray 2. 20 the boom should be isolated as much as possible from variations in ground contour that produce boom instability, whilst maintaining consistent height of the boom above the crop across the full width of the boom.

A need exists for a small to medium sized boom, in the 12 to 18 metre range, for spraying smaller paddock- n rocky, undulating terrain where larger booms become impractical. Booms of this size are available, but they are not as robust or easily transportable as their smaller size would suggest. Some known booms are designed to fold to a transport position, however the operator must still walk long distances around the boom to complete the folding operation, and must frequently handle the boom, increasing the chances of exposure to dangerous chemicals.

The present invention was developed with a view to providing a boom for spraying apparatus which is particularly, though not exclusively, in the small to medium size range and

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r i i 3 which is better adapted to overcome at least some of the problems noted above.

According to the present invention there is provided a boom for spraying apparatus, the boom comprising: a pair of elongate towing members pivotally connected to each other at one end for towing the boom behind a vehicle; a pair of wheels mounted on the boom; first and second boom arms pivotally connected to the respective other ends of the towing members, proximate an outer end of the respective boom arms, the inner ends of the respective boom arms being pivotally connected to each other whereby, in use, the boom arms and the towing members can be pivoted between an operating position of the boom in which the first and second boom arms lie substantially transverse to a direction of travel, and a transporting position of the boom in which the boom arms and towing members together form a substantially diamond shape.

Preferably the boom further comprises first and second boom wings pivotally connected to said outer ends of the respective first and second boom arms, said boom wings being adapted to also lie substantially transverse to the direction S of travel in the operating position. Advantageously said boom wings can pivot in a forwards direction to lie substantially parallel to said towing members in the transporting position.

Preferably said pivotal connection of the boom wings to the boom arms is in the form of a break-away connection whereby, if a boom wing should strike object in the operating position it can "break-away" fro. the boom arm and thereby minimise structural damage to the remainder of the boom.

Advantageously each wheel of said pair of wheels is mounted proximate said respective other ends of the towing members, and is capable of pivoting about a vertical axis to reorientate the wheel when pivoting the boom arms and the towing members between said operating position and said transporting position or vice versa. In the preferred embodiment each wheel is supported on an upright member via a carrier arm and a suspension arm, said carrier arm being fixed -4rigidly to, and angled with respect to, said upright member, said suspension arm is pivotally connected at one end to the free end of the carrier arm to form an elbow and is pivotally connected to the axis of the wheel at the other end whereby, in use, the wheel axis can pivot about said elbow. Preferably shock absorbing means are provided between said upright member and the wheel axis for absorbing rapid movement of the wheel axis as it pivots about said elbow, in use.

In order to enable the reader to more fully ascertain the nature of the invention, a preferred embodiment of the boom according to the invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a preferred 15 embodiment of the boom according to the invention shown in an operating position; Figure 2 is a perspective view of the boom of Figure o 1 shown in a transporting position; Figure 3 is a plan view of the boom of Figure 2, shown in the transporting position; .o Figure 4 is a plan view of the boom of Figure 1 shown S. in its operating position; Figure 5 is an enlarged side view of one of the wheels and its manner of support on the boom illustrated in Figures 1 and 2; Figures 6 and 7 are a plan view and rear view respectively of the wheel suspension, also visible in Figure Figure 8 illustrates the manner in which a boom wing is pivotally connected to a boom ar11 of the boom illustrated in Figures 1 and 2; and, Figure 9 is a bottom view of the break-away pivotal connection between the boom wing and boom arm of Figure 8.

Figures 1 to 4 illustrate the preferred embodiment of a boom 10 for spraying apparatus of the kind commonly referred to as a boomspray (spray nozzles, pipes and hoses are omitted for clarity). The boom 10 comprises a pair of elongate towing members 12 pivotally connected to each other at one end 5 14 for towing the boom behind a vehicle. The boom further conmprises a pair of wheels 16, and first and second boom arms 18 pivotally connected to the respective other ends 20 of the towing members 12, proximate an outer end of the respective boom arms 18. The inner ends of the boom arms 18 are pivotally connected to each other at pivotal connection 22 so that, in use, the boom arms 18 and the towing members 12 can be pivoted between an operating position of the boom as illustrated in Figures 1 and 4, in which the first and second boom arms 18 lie substantially transverse to a direction of travel, and a transporting position of the boom illustrated in Figures 2 and 3 in which the boom arms 18 and towing members 12 together form a substantially diamond shape.

The boom 10 further comprises first and second boom wings 24 which are pivotally connected to the outer ends of the respective first and second boom arms 18. The boom wings 24 are adapted to also lie substantially transverse to the direction of travel in the operating position, as illustrated o in Figures 1 and 4. The boom wings 24 can pivot in a forwards direction to lie substantially parallel to the towing members 12 in the transporting position, as illustrated in Figures 2 and 3. The boom wings 24 remain locked to the towing members 12 in the transporting position, for example, by engaging with hooks provided for that purpose on the towing members 12 near the pivotal connection 14. In this embodiment, the pivotal connection 14 is provided with a conventional trailer coupling arrangement for connection with a standard tow ball on a towing vehicle (not illustrated).

The wheels 16 are mounted proximate the respective other ends 20 of the towing members 12, and are capable of pivoting about a vertical axis to reorientate the wheel as required. The operation of pivoting the boom arms 18 and towing members 12 between the operating position illustrated in Figure 1 and the transporting position illustrated in Figure 2, can be performed simply and rapidly as follows. The operator steps over one of the towing members 12 into the triangular area bounded by the towing members 12 and the boom arms 18. Both of the wheels 16 are then pivoted manually about 6 a vertical axis so as to be substantially perpendicular to the plane of the respective towing member 12, so that the towing members 12 are free to pivot on the wheels in an arc about the pivotal connection 14. The pivotal connection 22 of the boom arms 18 is released from a locked condition in the operating position of the boom 10 and then the boom arms 18 and towing members 12 are simultaneously pivoted so that the respective other ends 20 of the towing members are drawn inwards towards each other, whereas the pivotal connection 22 of the boom arms 18 moves outwards in the direction of arrow A in Figure 1 to S- form a diamond shape as illustrated in Figures 2 and 3.

The pivotal connection 22 can then be locked in the transporting position of the boom 10 and wheels 16 are again pivoted -o as to be substantially parallel to the direction of towing. Finally, the boom wings 24 are pivoted forwards so as to be substantially parallel to the towing members 12 in the transporting position. The whole operation can be effected o with a minimum of effort from within the diamond shaped area bounded by the towing members and boom arms 18. Therefore the operator is saved from having to walk long distances around the boom to fold it to its transporting position or operating o position, and the opportunities for contacting dangerous chemicals are minimised. In order to pivot the towing members 12 and boom arms 18 from a transporting position to an operating position, essentially the same procedure is followed in reverse.

It will be immediately apparent that the above described arrangement of the boom 10 also enables maximum advantage to be obtained from the variation in spacing between the wheels 16 in the operating and transporting positions. In the operating position the large spacing between the wheels 16 provides enhanced stability for the boom 10, whereas in the transporting position the reduced distance between the wheels means that the total width of the boom need be no larger than the width of a conventional towing vehicle such as a four wheel drive or tractor, and therefore can be safely towed on the road and through standard width gateways.

Towing members 12 are constructed in a similar manner

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-7to a roof truss, having -riangular bracing for both rigidity and strength, and are manufactured of light gauge galvanised tube. One of the towing members 12 is welded at said one end 14 to a drawbar plate 25, whilst the other towing member is pivotally connected at said one end 14 to the drawbar plate The boom arms 18 are constructed with a triangular prism structure comprising first and second horizontal beams 26, 28 welded to two vertical uprights 30, 32 at their respective ends 0[ to form a square frame. Two horizontal struts 34, 36 extend at an angle from the top and bottom respectively of the outer vertical upright 32 to join with a third vertical upright 38 (see Figures 1 and Finally, two diagonal stays 40 extend from the top of uprights 38 and 32 respectively to the bottom of the inner upright 30 of each main boom arm 18. Typically, the bottom horizontal beam 26, the bottom horizontal strut 36 and the three vertical uprights 30, 32 and 38 are 50mm, square 2mm rectangular hollow section (RHS) galvanised steel tube.

The top horizontal bctm 26 and horizontal strut 34, as well as diagonal stays 40 arp made from smaller 25 x 50mm RHS. This triangular prism frame construction of the main boom arms 18 provides both strength and rigidity whilst being relatively light-weight, to form a chassis for the boom.

The pivotal connection 22 of the boom arms 18 is formed by two hinge connections at the top and bottom respectively of the inner vertical uprights 30 of the boom arms. The same type of hinge connections are used for connecting the outer ends of the boom arms and the towing members 12, as illustrated in Figure 5. Each hinge connection is formed by a trailer perch block 42 straddled by a trailer shackle bracket 44 and held together by a high tensile pin 46 which passes through a nylon bush (not visible).

In the operating position of the boom 10 a first horizontal stay 48, which is pivotally connected to the drawbar plate 25, engages a first ball pivot 50 provided on the lower horizontal beam 26 of one of the boom arms 18 adjacent an inner end, and locks the boom arms 18 so that they remain substantially transverse to the direction of travel as illustrated in Figures 1 and 4. A second horizontal stay 52

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L 8 extends substantially perpendicularly from the first stay 48 at a point adjacent the coupling for ball pivot 50 and is pivotally connected at its other end to the lower horizontal beam 26 of the boom arm 18 at a pivot point 53 remote from said ball pivot 50 and adjacent an outer end of the boom arm 18.

When moving the boom from the operating position to its transporting position, the first stay 48 is unhitched from ball pivot 50 and, when the towing members 12 have been pivoted o. inwards to the transporting position, the first stay 48 can be coupled to a second ball pivot 55 provided on one of the towing members 12 adjacent the end 20. The second stay 52 remains coupled to the opposite boom arm 18 at pivot point 53 and provides a rigid connection to lock the boom arms 18 and towing members 12 in the transporting position, and prevent them from S 15 moving apart during transport.

,The boom wings 24 are of simple triangular frame construction and are typically manufactured from welded lengths .of 30 or 35mm square RHS. Advantageously the pivotal connection of the boom wings 24 to the boom arms 18 is in the form of a break-away connection as illustrated in Figures 8 and o 9. At its top end the vertical upright 54 of the boom wing is o pivotally connected to the upright 32 of the boom arm 18 by means of a ball and socket joint 56 which allows the upright 54 to pivot in virtually any direction, including away from the vertical. At its bottom end the upright 54 is held parallel to the upright 32 by means of first and second pivot pins 58 received in a frame pivot plate 60. Frame pivot plate 60 is provided with two open ended slots 61 within which pins 58 are slidably received and held by means of tension spring 62.

Spring 62 is anchored at one end to the bottom horizontal beam 26 of the boom arm 18 by a chain 64 that engages a chain lock plate 66, and at the other end by a connecting bolt 67 provided in wing pivot plate 68.

In the operating position of the boom, pivot pins 58 are normally held in slots 61 by spring 62 and keep the boom wing 24 extending substantially collinearly with its associated boom arm 18. If during operation the boom wing 24 should encounter an obstacle the boom wing is free to pivot on ball 9 joint 56 and either one of pivot pins 58, and if necessary the boom wing will "break-away" at one of the slots 61 against the force of spring 62. Pivot pins 58 act to quickly restore the boom wing 24 to its correct position under the force exerted by spring 62. Substantially the same "break-away" action occurs should the boom wing 24 inadvertently strike the ground, applying an upwardly acting turning moment to the boom wing so that pivot pins 58 slide outwardly in the slots 61 of pivot plate 60. In an extreme case the pivot pins 58 may both escape from the slots 61 of pivot plate 60 and the boom wing will then be left suspended from the ball joint 56. It is a relatively simple operation, once the boom 10 has been restored to level ground to reinsert the pivot pins 58 in slots 61 of pivot plate The boom wing 24 automatically realigns itself by virtue 15 of the spaced location of the pivot pins 58. Tension spring 62 is selected to be sufficiently stiff to prevent the boom wings 24 from rocking or swaying during normal operation. The Stension of spring 62 can be adjusted by changing the position of the links of chain 64 in chain lock plate 66.

An important feature of the described embodiment of the boom 10 is the manner in which wheels 16 are pivotally S connected thereto. Figures 5, 6 and 7 illustrate the pivotal connection of the wheel 16 and the wheel suspension. Bcth of the wheels 16 are supported on a main vertical upright 70, of heavier gauge 75mm square RHS. Upright 70 is pivotally connected on the one hand to the third upright 38 of one of the boom arms 18, and on the other hand to the vertical upright 72 of one of the towing members 12. The pivotal connections of the main upright 70 to the boom arm 18 and the towing member 12 are in the form of hinge connections substantially identical to the hinge connections of the pivotal connection 22 between the boom arms 18, and will not be described in detail again.

The same reference numerals are used to identify the identical parts.

Wheel 16 is rotatably supported on the upright 70 via a carrier arm 74 and a suspension arm 76. Carrier arm 74 is fixed rigidly at an angle of approximately 450 to the vertical upright 70, and is typically manufactured from 65mm square RHS.

10 Suspension arm 76 is pivotally connected at one end to the free end of the carrier arm 74 to form an elbow 78 and is pivotally connected to the wheel axle 80. Therefore, the wheel 16 is free to pivot about elbow 78. The pivotal connection at elbow 78 is provided by a tapered roller suspension bearing taken from a trailer hub, and together with shock absorber 82 provides excellent suspension for wheels 16. Shock absorber 82 is pivotally connected at one end to the wheel axle 80 and is fixed at its top end to the main i right 70, and may be an ordinary air or spring shock absorber from, for example, a motor cycle. The shock absorbers 82 absorb any sudden vertical movement of the wheel 16 due to variations in the ground surface, and therefore improves the stability of the boom by minimising the extent to which such ground variations are transmitted to the boom.

The entire wheel and suspension assembly connected to the main upright 70 is pivotable about a vertical axis by S virtue of the pivotal connections of the main upright to the S respective boom arm 18 and towing member 12. It can be seen that upright 70 can pivot through at least the approximately 900 required when pivoting the towing members 12 and boom arms 18 between their transporting and operating positions. Wheel 16 can be locked in the appropriate angular position by means of a spring-loaded dog bolt (not illustrated) which has a tapered end received in one of a plurality of apertures provided in a lock plate (also not illustrated) provided on either one of the upright 38 of boom arm 18 or upright 72 of towing member 12.

Both of the main uprights 70 on which wheels 16 are supported, are also provided with a winder 84 at the top end thereof which is connected to a threaded rod (not shown) housed within the upright 70 for adjusting the height of the boom above ground. Thus, the height of the boom 10 can be conveniently adjusted by the operator before or after folding the boom arms 18 and the towing members 12 from the transporting position to the operating position, or vice versa.

Now that a preferred embodiment of the boom 10 for a boom spray has been described in detail it will be apparent ic~ ~I 1- 11-- -11that the boom 10 has a number of significant advantages over prior art booms, particularly in the small to medium size range. The boom 10 is of simple and robust construction, and uses commonly available parts and materials. As the boom is largely constructed of light gauge RHS galvanise tubing, the weight of the entire boom can be kept to a minimum, for example, as little as 250kg. The boom can be easily folded' between its operating and transporting positions by a single operator, who can perform the whole operation standing within the area bounded by the boom arms 18 and towing members 12.

The pivoting arrangement of the boom arms and the towing members takes full advantage of the improved stability afforded S by the wider spacing of the wheels in the operating position, and the improved manoeuvrability afforded by the close spacing %O0" 15 of the wheels in the transporting position.

Numerous variations and modifications will suggest themselves to pcrsons skilled in the manufacturing arts, other than those already described, without departing from the basic inventive concepts. For example, whilst the triangular prism frame construction of the boom arms 18 is particularly advantageous in view of its light weight, strength and rigidity, it is obvious that any suitable structure could be employed for the boom arms 18 forming the main chassis of the boom 10. All such variations and modifications are to be considered within the scope of the present invention, the nature of which is to be determined from the foregoing description and the appended claims.

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Claims (7)

1. 2. A boom for spraying apparatus as claimed in claim 1, further comprising first and second boom wings pivotally connected to said outer ends of the respective first and second boom arms, said boom wings being adapted to also lie substantially transverse to the direction of travel in the operating position.
2. 3. A boom for spraying apparatus as claimed in claim 2, wherein said boom wings can pivot in a forwards direction to lie substantially parallel to said towing members in the transporting position.
3. 4. A boom for spraying apparatus as claimed in claim 3, wherein said pivotal connection of the boom wings to the boom arms is in the form of a break-away connection whereby, if a boom wing should strike an object in the operating position it can "break-away" from the boom arm and thereby minimise structural damage to the remainder of the boom. A boom for spraying apparatus as claimed in any one of the preceding claims, wherein said boom arms have a 13 triangular prism construction forming a rectangular frame, and said pivotal connection of the inner ends of the boom arms is formed by two hinge connections at the top and bottom respectively on an inner vertical upright of each boom arm.
4. 6. A boom for spraying apparatus as claimed in any one of the preceding claims, further comprising a pivotable stay which is movable between a first position in which it locks the boom arms and the towing members in the operating position, and a second position in which is locks the boom arms and the towing members in the transporting position.
5. 7. A boom for spraying apparatus as claimed in any one of the preceding claims, wherein each wheel of said pair of wheels is mounted proximate said respective other ends of the towing members, and is capable of pivoting about a vertical axis to reorientate the wheel when pivoting the boom arms and the towing members between said operating position and said transporting position or vice versa.
6. 8. A boom for spraying apparatus as claimed in claim 7, bq, wherein each wheel is supported on an upright member via a carrier arm and a suspension arm, said carrier arm being fixed rigidly to, and angled with respect to, said upright member, said suspension arm is pivotally connected at one end to the free end of the carrier arm to form an elbow and is pivotally connected to the axis of the wheel at the other end whereby, 25 in use, the wheel axis can pivot about said elbow.
7. 9. A boom for spraying apparatus as claimed in claim 8, wherein shock absorbing means are provided between said upright member and the wheel axis for absorbing rapid movement of the wheel axis as it pivots about said elbow, in use. i L I 4 14 A boom for spraying apparatus substantially as herein described with reference to and as illustrated in the accompanying drawings. Dated this 20th day of August 1993. DARRYL JAMES MARTIN By Its Patent Attorneys GRIFFITH HACK CO. Fellows Institute of Patent Attorneys of Australia. a 4 B I. 4 I- I~ 15 ABSTRACT A boom (10) for spraying apparatus of the kind commonly referred to as a boomspray, comprises a pair of elongate towing members (12) pivotally connected to each other at one end (14) for towing the boom hind a vehicle. The boom further comprises a pair of wheels and first and second boom arms (18) pivotally connected to the respective other ends of the towing members proximate an outer end of the respective boom arms The inner ends of the boom arms (18) are pivotally connected to each other at pivotal connection (22) so that, in use, the boom arms (18) and the towing members (12) can be pivoted between an operating position of the boom, in which the first and second boom arms (18) lie substantially transverse to the direction of travel, and a transporting position of the boom, in which the boom arms (18) and towing members together form a substantially diamond shape. First and second boom wings (24) are pivotally connected to the outer ends of the respective first and second boom arms and are adapted to also lie substantially transverse to the direction of travel in the operatiig position. The boom wings can pivot in a forwards direction to lie substantially parallel to the towing members (12) in the transporting position. 06. -I