Abstract:
A guide system for use with breakaway cables of a sprayer boom of an agricultural sprayer is provided that may include multiple guides for the cables. One of the guides may provide a barrier to physical contact between the cables and the other guide or other potential pinch points to eliminate instances of breakaway cable pinching. This may be done by way of a guide tube through which the cable extends, with the guide tube preventing physical contact between the cable and a pair of rollers of a roller guide.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates generally to agricultural product application equipment such as self-propelled agricultural sprayers and, in particular, to a guide system for breakaway cables of an agricultural sprayer boom. 
       BACKGROUND OF THE INVENTION 
       [0002]    Sprayer boom lengths are increasing over time to allow increased coverage in a single spraying pass. Longer boom lengths can lead to relatively more vertical movement of the boom tip ends while the booms flex during use and during tilting or roll movements of the sprayer. This vertical movement can cause the boom tip ends to contact the ground during touchdown events. Touchdown events can also occur when the ground under the tip ends of booms is at a greater height than the ground over which the sprayer wheels are driving. To help protect the booms during touchdown events, some booms have breakaway boom sections at their ends that are supported by breakaway joints. The breakaway joints are configured to absorb impact energy by allowing breakaway boom sections to pivot upwardly and/or rearwardly during touchdown events. Some breakaway boom sections are able to pivot in both forward and rearward directions and are biased toward centered or neutral positions by springs at the breakaway joints. Some breakaway joints have a pair of cables with ends connected to a tension spring. Opposite ends of the cables are connected to ends of a breakaway lever attached to the breakaway boom section. This allows movement of the breakaway boom section in either forward or rearward directions during a touchdown event to further load the tension spring, which restores the breakaway boom section to the neutral position after the touchdown event. The cables are routed through a roller guide that has a pair of rollers held between a pair of plates. The rollers guide the cables so that the cables pull the tension spring in a generally straight line regardless of the position of the breakaway boom section. However, during particularly forceful touchdown events, the cables may whip or jerk and move toward ends of the rollers. Over time, some cables start to track toward the ends of the rollers. Eventually, the cables can work their way off the ends of the rollers and get stuck in or damaged by being pulled through a narrow gap between the rollers and the plates of the roller guide. When the cables get stuck, the breakaway joint no longer works because movement in at least one direction may be stopped. Cables that are damaged may fail earlier than they would otherwise, which compromises the function of the breakaway joint. Compromised or nonfunctional breakaway joints can lead to damage of boom tip components and other boom components during touchdown events. 
       SUMMARY OF THE INVENTION 
       [0003]    A guide system for use with breakaway cables of a sprayer boom of an agricultural sprayer is provided that allows for a breakaway joint with straightforward construction and trouble-free breakaway cable operation. The guide system may include multiple guides, with one of the guides providing a barrier to physical contact between a cable and the other guide or other potential pinch points to eliminate instances of breakaway cable pinching. This may be done by way of a guide tube through which the cable extends, with the guide tube preventing physical contact between the cable and a pair of rollers. 
         [0004]    According to one aspect of the invention, a guide system for use with a breakaway cable of a sprayer boom of an agricultural sprayer is provided. The sprayer boom includes a first boom section and a second boom section defining a breakaway boom section of the sprayer boom with a breakaway joint having a breakaway cable extending between the first boom section and the breakaway boom section for controlling movement of the breakaway boom section with respect to the first boom section. The guide system includes a first guide supported relative to the first boom section and has an interior passage extending generally in alignment with the first boom section. A second guide extends through the interior passage of the first guide. The breakaway cable extends through an interior passage of the second guide, and the second guide is configured to move with respect to the first guide and the first boom section during movement of the breakaway boom section with respect to the first boom section. 
         [0005]    According to another aspect of the invention, the first guide is supported in a fixed position relative to the first boom section. The second guide may be configured to slide in a longitudinal direction through the interior passage of the first guide. The cable may be one of a pair of cables that extends between the first boom section and the breakaway boom section and through the second guide. 
         [0006]    According to another aspect of the invention, the first guide may be a roller guide that has a pair of spaced apart rollers arranged on opposite sides of the second guide to limit transverse movement of the second guide. 
         [0007]    According to another aspect of the invention, the second guide may be a guide tube with a circumferential sidewall extending about an interior passage of the second guide. The guide tube may have first and second ends on opposite sides of the roller guide and the first and second ends of the guide tube may move relative to the rollers of the roller guide while the breakaway boom section moves with respect to the first boom section. 
         [0008]    According to another aspect of the invention, a breakaway lever extends from the breakaway boom section with the breakaway lever and has a first lever end arranged beyond a first side of the breakaway boom section and a second lever end arranged beyond a second side of the breakaway boom section. The pair of cables is respectively connected to the first and second lever ends. Deflection of the breakaway boom section in a first direction moves the first lever end toward the first boom section, and deflection of the breakaway boom section in a second direction moves the second lever end toward the first boom section. Movement of the breakaway lever causes movement of the guide tube with respect to the rollers of the roller guide, which may include pulling the guide tube relatively farther through the roller guide. 
         [0009]    According to another aspect of the invention, a spring is supported by the first boom section for biasing the breakaway boom section to a neutral position. The guide tube may be aligned with the spring and the pair of cables may be connected to the spring at an outer end of the guide tube. The outer end of the guide tube may face toward the spring and may be attached to the spring. The ends of the pair of cables and the outer end of the guide tube may move in unison with each other. 
         [0010]    According to another aspect of the invention, the guide system may include an anchor at the inner end of the guide tube. The ends of the pair of cables and the spring may be attached to the anchor. The anchor may be a fastener such as a bolt or a pin that extends in a transverse direction through the outer end of the guide tube. 
         [0011]    According to another aspect of the invention, the guide tube may have an inner end opposite the outer end. The outer end of the guide tube may have an opening that is wider than the interior passage of the guide tube. The inner end of the guide tube may taper toward a main body section of the guide tube. 
         [0012]    According to another aspect of the invention, a guide system is provided for use with breakaway cables of a sprayer boom of an agricultural sprayer. The sprayer boom may include a first boom section and a breakaway boom section arranged outwardly of and configured for relative movement with respect to the first boom section. A breakaway lever may be supported by and extend beyond opposite sides of the breakaway boom section. A pair of breakaway cables may connect the breakaway lever to a spring that biases the breakaway boom section to a neutral position relative to the first boom section while permitting deflection of the breakaway boom section relative to the first boom section during breakaway events. A roller guide may be arranged between the spring and the breakaway lever and provide a roller guide interior passage that is aligned with the spring. A guide tube may extend through the roller guide interior passage. The guide tube may have a sidewall that extends about a periphery of a guide tube bore through which the pair of breakaway cables extends. The guide tube is configured to move with respect to the roller guide and in unison with the pair of breakaway cables during movement of the breakaway boom section relative to the first boom section while moving between neutral and deflected positions of the breakaway boom section. 
         [0013]    According to another aspect of the invention, the roller guide may have a pair of spaced apart rollers arranged on opposite sides of the guide tube to engage the sidewall of the guide tube to direct the guide tube into substantially longitudinal movement. 
         [0014]    According to another aspect of the invention, an agricultural sprayer is provided with a chassis having wheels supporting the agricultural sprayer. A spray system may be supported by the chassis and may include at least one storage container storing a volume of product for spray delivery on to an agricultural field. A boom may extend from the chassis and support nozzles for delivering the product onto the agricultural field. The boom may include a first boom section arranged relatively closer to the chassis. A breakaway boom section may be arranged relatively farther from the chassis. The breakaway boom section may define a neutral position with the breakaway boom section extending generally longitudinally from the first boom section during normal operation and a breakaway position corresponding to the breakaway boom section being deflected away from the neutral position during breakaway events during which the breakaway boom section contacts the ground. A breakaway joint may be arranged between the first boom section and the breakaway boom section and be configured to permit the breakaway boom section to move with respect to the first boom section during breakaway events and bias the breakaway boom section back to the neutral position after breakaway events. The breakaway joint may include a breakaway lever that extends from the breakaway boom section with the breakaway lever having a first lever end arranged beyond a first side of the breakaway boom section and a second lever end arranged beyond a second side of the breakaway boom section. A spring may be supported by the first boom section for biasing the breakaway boom section to the neutral position. A first breakaway cable may be connected to the spring and its outer end may be connected to the first end of the breakaway lever. A second breakaway cable may be connected to the spring and its outer end may be connected to the second end of the breakaway lever. A roller guide may be arranged between the spring and the breakaway lever and define a path along which the first and second breakaway cables extend from the first and second ends of the breakaway lever to the spring. A guide tube may be movably arranged within the roller guide and have a circumferential sidewall and a guide tube bore extending longitudinally through the guide tube inwardly of the circumferential sidewall. The guide tube may define a spring end facing the spring and be arranged for movement in unison with the spring and a lever end facing the breakaway lever and have a guide tube lever end opening that extends into the guide tube bore and receives the first and second breakaway cables. The first and second breakaway cables may extend angularly from the first and second ends of the breakaway lever into the guide tube lever end opening and through the guide tube bore. The guide tube may provide a barrier between the first and second breakaway cables and the roller guide. 
         [0015]    Other aspects, objects, features, and advantages of the invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings in which like reference numerals represent like parts throughout. 
           [0017]      FIG. 1  is a pictorial view of an agricultural sprayer with a guide system for breakaway boom cables according to the present invention; 
           [0018]      FIG. 2  is a simplified enlarged pictorial view of a breakaway joint of the agricultural sprayer of  FIG. 1 ; 
           [0019]      FIG. 3  is simplified partially schematic view of the breakaway joint of  FIG. 2  in a neutral position; and 
           [0020]      FIG. 4  is simplified partially schematic view of the breakaway joint of  FIG. 2  in a deflected position. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    Referring now to the drawings and specifically to  FIG. 1 , a guide system  5  for guiding breakaway cables of a breakaway joint  7  of a boom  9  is shown that reduces the likelihood of breakaway cable damage and helps prevent damage to boom tip components. Guide system  5  and boom  9  are shown incorporated on an agricultural sprayer. The agricultural sprayer is shown here as a self-propelled agricultural sprayer vehicle or self-propelled sprayer  11 , which is shown here as a rear-mounted boom self-propelled sprayer, although it is understood that self-propelled versions of sprayer  11  can have either rear-mounted or front-mounted booms. Sprayer  11  may include those available from CNH Industrial, including the Case IH Patriot Series sprayers. 
         [0022]    Still referring to  FIG. 1 , sprayer  11  has a chassis that includes frame  13  that supports various assemblies, systems, and components. These various assemblies, systems, and components include cab  15 , engine  17 , and a hydraulic system that receives power from engine  17  and includes at least one hydraulic pump which may be in a hydrostat arrangement for providing hydraulic pressure for operating hydraulic components within the hydraulic system. For sprayers  11  with hydrostatic drives, hydraulic motors are operably connected to the hydraulic pump(s) for rotating wheels  19 . In mechanical drive applications, a mechanical transmission receives power from engine  17  and delivers power for rotating wheels  19  by way of power-transmitting driveline components, such as drive shafts, differentials, and other gear sets in portal, drop boxes, or other housings. Spray system  21  includes storage containers such as product tank  23  that stores a volume of product  25  for delivery onto an agricultural field with sprayer  11 . Product  25  includes any of a variety of agricultural liquid products, such as various pesticides, herbicides, fungicides, liquid fertilizers, and other liquids including liquid suspensions beneficial for application onto agricultural fields. A product delivery pump conveys product  25  from product tank  23  through plumbing components such as interconnected pieces of tubing and through a boom tubing system for release out of spray nozzles that are spaced from each another along the width of boom  9  during spraying operations of sprayer  11 . 
         [0023]    Still referring to  FIG. 1 , boom  9  includes multiple boom sections  27  connected longitudinally to provide the corresponding width of the assembled boom  9 . Boom sections  27  include center section  29  and left and right boom arms extending in opposite directions from center section  29 . Left and right boom arms have multiple sections with pairs of inner boom sections  31 , mid boom sections  33 , and outer or breakaway boom sections  35  extending in opposite directions along the respective left and right boom arms mirrored about a longitudinal axis of the sprayer  11 . The corresponding left and right sections of the pairs of inner, mid, and breakaway boom sections  31 ,  33 ,  35  are substantially identical, so only one will be described, with the description applying to both the left and right sections of left and right boom arms. At each of the left and right boom arms, an inner end of inner boom section  31  is pivot-connected with hinge  37  to center section  29  and an outer end is pivot-connected with hinge  39  to an inner end of mid boom section  33 . Breakaway joint  7  includes at least one hinge  41  that interconnects an outer end of mid boom section  33  to an inner end of breakaway boom section  35 . The hinges  37 ,  39  and breakaway joint  7  between the respective inner, mid, and breakaway boom sections  31 ,  33 ,  35  allow the boom  9  to collapse by folding into a non-use or stored folded position for transportation. Although boom  9  is shown with three sections at each of the left and right boom arms that can fold generally horizontally, the number of sections and the direction of folding can be different such as a single section or two sections and a generally vertical folding direction to collapse the boom  9  into the stored folded position. 
         [0024]    Referring now to  FIGS. 1 and 2 , breakaway joint  7  is configured to absorb impact energy by allowing breakaway boom section  35  to deflect during touchdown events during which the boom section  35  touches the ground or other obstacle. During deflection, the breakaway boom section  35  moves through articulation of the breakaway joint  7  away from a neutral position ( FIGS. 1 and 3 ) in which the breakaway boom section  35  extends straight outwardly from the rest of the boom  9  to a breakaway position in which the breakaway boom section  35  extends at an angle with respect to the rest of the boom  9  ( FIG. 4 ). Hinge(s)  41  of the breakaway joint  7  is arranged with respect to the breakaway boom section  35  to allow the breakaway boom section  35  to move relative to the rest of the boom  9  such as to pivot vertically or horizontally. Hinge(s)  41  defines a pivot axis that may be arranged tilted away from vertical so that deflection moves the breakaway boom section  35  with both a horizontal and vertical component, such as both rearwardly and upwardly. 
         [0025]    Referring to the simplified representation of the components in  FIG. 2 , breakaway joint  7  includes spring  43  and breakaway lever  45  arranged at opposite sides of hinge  41 . Spring  43  is shown arranged inwardly of the hinge  41 , connected to mid boom section  33 . Breakaway lever  45  is shown arranged outwardly of hinge  41 , connected to breakaway boom section  35 . Breakaway lever  45  includes first lever end  47  arranged beyond a first side of the breakaway boom section  35 , shown in front of breakaway boom section  35 . A second lever end  49  is arranged beyond a second side of the breakaway boom section  35 , shown behind the breakaway boom section  35 . At least one cable  51  connects spring  43  to breakaway lever  45  so that movement of breakaway boom section  35  is translated through cable  51  to pull against spring  43  when breakaway boom section  35  deflects during touchdown events. As shown, a pair of cables  51  connects spring  43  to the first and second lever ends  47 ,  49  of breakaway lever  45  to translate movement of breakaway boom section  35  into loading of spring  43  during deflection. The loaded spring  43  biases breakaway boom section  35  back to the neutral position after the deflection or touchdown event by pulling against the cables  51  with a restorative force. 
         [0026]    Still referring to  FIG. 2 , guide system  5  contains and directs movement of at least portions of the cable(s)  51  so that the cable(s)  51  actuates spring  43  along a substantially straight-line path regardless of movement characteristics of breakaway boom section  35 . Guide system  5  includes multiple guides, shown as guides  53 ,  55 . Guide  53  is a first or outer guide  53  that is supported in a fixed position relative to the boom  9 , such as mounted to mid boom section  33 . Guide  55  is a second or inner guide  55  that is configured to cover at least portions of the cable(s)  51  and move with respect to guide  53  to provide a barrier to direct contact between cable(s)  51  and outer guide  53 , which prevents binding between cable(s)  51  and outer guide  53 . 
         [0027]    Still referring to  FIG. 2 , outer guide  53  defines a roller guide  57  with a central opening or interior passage, shown as roller guide interior passage  59 , that is aligned with and faces spring  43 . Roller guide  57  has a pair of horizontally arranged brackets  61  and a pair of vertically arranged spaced-apart rollers  63  that collectively extend around roller guide interior passage  59 . Rollers  63  are supported by the brackets  61 , with a lower bracket  61  connected to the mid boom section  33  so that the roller guide  57  extends upwardly from the mid boom section  33 . 
         [0028]    Still referring to  FIG. 2 , inner guide  55  defines a guide tube  65  that has a main body  67  with a sidewall such as circumferential sidewall  69  that extends around a central opening or interior passage of guide tube  65 , shown as guide tube bore  71 . Guide tube  65  has a first or inner end shown as spring end  73  that faces spring  43  and a second or outer end shown as bracket end  75  that faces breakaway lever  45 . Anchor  77  is arranged at the inner or spring end  73  of guide tube  65  and is configured to connect guide tube  65  to spring  43 . Anchor  77  is shown having fastener  79  such as a bolt or pin that extends transversely across opposite sides of circumferential sidewall  69 , through guide tube bore  71  at the spring end  73  of guide tube  65 . Fastener  79  provides a common mounting structure for connecting a hook segment at an outer end  83  of spring  43  and cable ends  85  of cables  51  that may include cable thimbles or eye-type cable end hardware, locking the spring  43 , cables  51 , and guide tube  65  to each other. In this way, the tube  65  is a rigid sheath that surrounds portions of cables  51  and moves in unison with spring  43  and cables  51 . Outer or bracket end  75  of guide tube  65  defines a conical or taper segment  87  that tapers down toward the main body  67 . Taper segment  87  provides an opening  89  that is wider than the interior passage or guide tube bore  71  of guide tube  65  and through which the cables  51  extend into guide tube  65 . Taper segment  87  provides a frusto-conical lip that tapers in the same direction and approximately the same amount as an angle defined between the cables  51  as the cables  51  converge from the first and second lever ends  47 ,  49  of breakaway lever  45  toward guide tube  65 . 
         [0029]    Still referring to  FIG. 2 , inner guide  55  extends through the interior passage of outer guide  53  by way of guide tube  65  extending through roller guide interior passage  59  of roller guide  57 . The inner and outer or spring and bracket ends  73 ,  75  of guide tube  65  are arranged on opposite sides of the roller guide  57 . Rollers  63  of roller guide  57  limit transverse movement of guide tube  65  by engaging the sidewall  69  while permitting longitudinal movement of the guide tube  65  through the roller guide  57 . The substantially longitudinal movement of guide tube  65  coincides with lengthening and shortening of spring  43  during loading and unloading of spring  43 , which occurs during touchdown or breakaway-type deflection events of breakaway boom section  35  and the corresponding recovery of breakaway boom section  35  to the neutral position. 
         [0030]    Referring now to  FIGS. 3 and 4 , in light of the above, regardless of the position of breakaway boom section  35  and, thus, the amount of articulation at breakaway joint  7 , guide tube  65  loosely sheathes the cables  51  and prevents direct contact of cables  51  with the roller guide  57  by providing a floating tubular barrier that moves with spring  43 . 
         [0031]    Referring now to  FIG. 4 , during boom touchdown or deflection events, breakaway boom section  35  pivots away from its neutral position through articulation of breakaway joint  7 , which swings the breakaway lever  45  along an arcuate path, defined by the axis of hinge  41  of breakaway joint  7 . Movement of the first and second lever ends  47 ,  49  of breakaway lever  45  pulls the cables  51 , which further loads and increases the tension in spring  43  by pulling and extending it. Guide tube  65  moves in unison with spring  43 , substantially longitudinally through roller guide  57 . During touchdown or deflection, the tendency of guide tube  65  depicted about its point of contact with a roller(s)  63  in the roller guide  57  to follow the transverse component of the arcing motion of breakaway lever  45  is mitigated by the resistive force of spring  43  biasing the inner or spring end  73  of guide tube  65  in a substantially straight-line path aligned with mid boom section  33 . This may limit pivoting of guide tube  65  about its contact point with the roller(s)  63  in the roller guide  57  to less than about 20 degrees from its neutral position, whereby the cables  51  may pivot over the end edge of taper segment  87  at the outer or bracket end  75  of guide tube  65  while the guide tube  65  slides longitudinally through roller guide  57  in preference to pivoting the guide tube  65  within roller guide  57 , while preventing direct contact of cables  51  with roller guide  57 . 
         [0032]    Many changes and modifications could be made to the invention without departing from the spirit thereof. The scope of these changes will become apparent from the appended claims.